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CLEARING LAND 
OF STUMPS 




Published by 

The Institute of Makers of Explosives 

io3 Park Avenue, New York City 



CLEARING LAND 
OF STUMPS 




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Published by 
The Institute of Makers of Explosives 

103 Park Avenue, New York City 



Copyright 1917 by 
The Institute of Makers of Explosives 



^\.^V 



INSTITUTE 

OF 

MAKERS OF EXPLOSIVES 

Organized July 15, 1913 

MEMBERS 

AETNA EXPLOSIVES COMPANY, Inc. 
New York, N. Y, 

ATLAS POWDER COMPANY 
Wilmington, Del. 

AUSTIN POWDER COMPANY 
Cleveland, Ohio 

THE GRASSELLI POWDER CO. 
Pittsburgh, Pa. 

E. I. DU PONT DE NEMOURS & CO. 
Wilmington, Del. 

EGYPTIAN POWDER COMPANY 

East Alton, 111. 

EQUITABLE POWDER MFG. CO. 
East Alton, 111. 

EXCELSIOR POWDER MFG. CO. 
Kansas City, Mo. 

THE GIANT POWDER CO., Cons. 
San Francisco, Cal. 

HERCULES POW^DER CO. 
Wilmington, Del. 

ILLINOIS POWDER MFG. CO. 
St. Louis, Mo. 

KING POWDER COMPANY 
Cincinnati, Ohio 

SENIOR POW^DER COMPANY 
Cincinnati, Ohio 

STANDARD POWDER CO. 
Philadelphia, Pa. 

UNITED STATES POWDER CO. 
Terre Haute, Ind. 

- '^"i^'.L rr!VIS10« 
tm 22 1819 



INTRODUCTORY 

THIS bulletin is published by The Institute of Makers 
of Explosives. The aim is to give the united con- 
clusions and the sum of the experiences to date of 
nearly all makers of explosives and of farmers who have 
dealt successfully with the problem of stumps in fields, 
roads or any land to be cleaned up. 

The material has been assembled so any phase of it 
will be available easily and quickly. Conflicts of opinion 
have been eliminated in favor of known facts and 
formulae. The bulletin is offered as a manual or hand- 
book for farmers, home and road builders, contractors, 
park makers and others who remove stumps from land, 
and as a textbook for students of agriculture. 

Readers will find that the recommendations are 
impartial, and that the suggestions on that part of the 
work which can be done best with explosives are par- 
ticularly complete. 



To Clear or not to Clear 

A "stump" may be defined as any kind of a growth that obstructs land, 
whether it is the butt of a cut tree, a tall snag, a living tree or a bunch 
of sprouts or brush. From the viewpoint of a farmer it is a stump if it ob- 
structs the plowing and other tillage of the land. 



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The sort of wreckage practically perfect stump blasting should give. The pieces are shattered so they 
are easy to handle and so they bum well. 



Before deciding to clear land, the owner should consider several features 

of the matter well. The reckless slaughtering of the timber has left in stumps 

many thousands of acres of land which is not fit for 

cultivation and that should go back into timber. 

When Not to Clear Such land, of course, should not be cleared. On the 

other hand it is folly to permit brush land which has 

good soil to lie idle when a hundred years will not 

develop profitable timber on it. 

Much land that is in woods now should be left so, for timber and for fuel. 
Every farm should have its timber tract, where the forest is conserved in a 
way to make it permanent. To cut young growth that will make good timber 
in a reasonable time is a mistake, no matter how good the soil is. Remember, 
too, the wind-break value of a piece of woods adjoining farm land, and consider 
the effect on land you now farm of taking away the protection afforded. 

Do not clear land where the soil is too stony to be cultivated to advan- 
tcige, or land that is exceptionally steep or incurably swampy. Do not clear 
when the profits would not justify the clearing. And do not clear when you 
can buy equally good improved land for less than the cost of clearing. 

There is a certain sentimental satisfaction in clearing and cleaning up 
one's own place, connecting fields and improving it generally, even though 
such improving will not add greatly to the actual money income from the 
crops. This will have a bearing in some instances. 

But hard-headed judgment should not be swayed too much by sentiment, 
for there are a good many thousands of acres that have been cleared and now 
are parts of farms, which it would be wise and profitable to plant to 



forest again. Lay out your clearing carefully. Include no corners, gullies or 
steep places you will afterwards neglect. And make sure your field is rightly 
placed in relation to the rest of the farm. 




A fertile looking field which could not possibly pay a net profit of more than half what it should 
so long as the stumps remain as they are. Two or three years' gain in crops, or less, would pay for 
the blasting out of the stumps. 

About new clearing there may be some question, but about taking out 
stumps in good cultivated land there can be none. There are stumps in fields 
and along fences, roads, hedges and on home grounds. There are pastures 
that are pastures and not wheat fields or orchards because cultivation among 
the stumps is too inconvenient. There are old fruit trees and old shade trees 
that are diseased and a menace. All these should come out, and the quicker 
they come out the better. 




Worth little even as pasture land, never rising in value, but potentially worth $100 an acre as soon as 
it is cleared. This is the sort of valley floor that makes splendid fields of oats, com, alfalfa and other hay. 



The Profit and Loss Account of Stumps 

The man who is taking up the farming of cut-over land knows that he 
cannot do much until the stumps are removed. But lest he be tempted to 
permit some of them to remain in the cultivated fields, as many men on older 
farms are doing, it is well to point out some of the losses which stumps cause 
and some of the gain which their removal brings. 

No farm is well ordered when its fields are foul, and no farmer commands 
the respect of his neighbors when stumps are crowding out 
his crops. The loss in self-respect probably is even more 
Appearance serious. 

In farming stumpy fields a man does not have that sense 

of having done his best, which is half the battle for success. 

Tool breakage is another source of loss caused by stumps. Plows and 

furrows are broken, mowing machines and binders are both broken and racked 

and in some cases the use of machinery is prevented. Heavy engine tools 

cannot be used at all where there are roots in the ground. 

Greater speed and ease of cultivation is a prime reason for taking out 
stumps. The use of gang plows, wide harrows and other modern labor- and 




When the stumps are as thick as the hay piles or the shocks of wheat or oats or com there is some- 
thing the matter with the farm system. They are boarders who never pay any bills. 

time-saving equipment and methods is practical and economical only on land 
that is clean, both above and below the surface. And such use is becoming 
of more and more importance, as farm wages go higher and labor becomes 
scarcer. 

The injury to horses often is much greater from a money standpoint. 
Spavins and sprains result from jerks against roots. Mares are caused to slink 
foals, young horses are made balky. The danger of injury to men is by no 
means absent. The kick of plow handles rupture many men, and every year 
sees its quota of broken arms and legs among farmers who try to plow, culti- 
vate or mow among stumps. 

Weed spread is a thing that must be charged up to stumps. They grow 
about the stumps, mature seed and pollute the whole farm. 



Just as the presence of stumps tends to lower the value of land and to 
keep it down, clearing off the stumps will raise it and keep it 
on the increase. Once start to clearing away the stumps on 
Increased your place and the neighbors and people who pass on the roads 
Production will take it for granted that the place is a paying proposition, 
worth developing. If you want to sell it, there is no surer way 
of adding a few hundred or a few thousand dollars to the sell- 
ing price. To hold stump land for increase in value is a mistake. Clear it up 
and force the increase. 

The actual gain in crops to be secured by the removal of stumps can be 
measured by the proportion of the total ground that they occupy. For 
instance, in many cases a stump takes up a square rod of ground. In meas- 
uring the value of the removal of stumps, the gain in crops and in speed and 
ease of working the ground should be compared, not with the total value of 
the crop, but with the net profit before stumps are removed. Thus, if a 




Tbiis is the typical appearance of much land that is very fertile and which would 
pay handsomely if in alfalfa or fruit. (Near Linville Falls, N. C.) 

25-bushel crop of wheat costs 20 bushels to grow, the addition of 5 
bushels to the yield will increase the net profit 100 per cent. Two dozen 
stumps to the acre may occupy such a large part of the acre that their 
removal will double the net profit. 

The clearing up of land can be made to mean something more than the 
financial profit it brings, for when properly handled it well can be made one 
of the links that hold the boys to the farm. Once a boy has helped to develop 
a property in a way that he enjoys he will remember that place as home as 
long as he lives. And boys will be enthusiastic over the clearing operations, 
with the necessary planning for new fields, the blasting and stump pulling, 
and the burning afterwards, if the work is managed along some of the newer 
lines which take out the drudgery. 

The Essentials of Good Stump Removing 

Before settling on a plan for removing stumps, it is well to have clearly 
before you just what is required. 

7 



The stumps must come out entirely, or at least deep enough so that roots 
never will catch plows or other implements. Stumps with roots must be dis- 
posed of as profitably as possible, used if possible, or burned cheaply. They 
often can be sold or used at home for firewood of some kind, or sold for extract 






'•* . *'. *»* •'<< 




When all the trees of a woods-lot are cut down, the ground seldom is protected from animals and 
so treated as to grow a new piece of forest. But it should either be put in forest or cleaned up 
and farmed. The green stumps should be left stand a season, then should be blasted out with about 
four charges each. They are almost impossible to pull economically. 



purposes. Failing this, they must be burned on the ground with as little dam- 
age to the soil as possible. In any case they must be broken into pieces small 
enough to handle by hand, unless derricks and power are to be used to handle 
them. 

The total money expense of the clearing project must be within the capi- 
tal available for the purpose, and the labor and time required must not exceed 
the supply. The condition in which the ground is left also is important. The 
holes should be shallow, and the less littering and tearing up of the surface 
there is, the better. The work usually should be finished in time for planting 
a crop in the spring, for the loss of a year's time costs money. 

These are the things which should be included in the plans for clearing. 

Nature of Stumps and Conditions Affecting 
Their Removal 

There are about 500 different varieties of trees which make stumps in 
America, and it is not advisable to classify them all in this bulletin. What 
is of value is to review the nature of their roots. 

There are three general types of roots — lateral roots, semi-tap roots and 
tap roots. (See cuts, pages 24 to 26.) Some varieties of trees always grow in one 
way; other varieties grow in either of two ways, depending on soil conditions. 
The stumps of some trees rot fast, while others are very durable. Some roots 
die when the trees are cut; others throw up sprouts. The wood of some roots 
is tough and can be twisted a great deal without breaking; of other varieties 
it is brittle and will break ofi when bent or jerked. 

8 



Typical tap-root stumps are long-leaf southern pine, hickory and black 
gum. Some of these trees grow a root that is almost as big as the trunk, ex- 
tending straight down into the ground. Others have slender 
roots. Sometimes these tap-roots send out lateral roots of 
Root Growth some size, but in other cases the laterals are limited to hun- 
dreds of short, hair-like rootlets growing from the main tap- 
root. The tap-root itself sometimes splits at a point several 
feet underground into several smaller roots, all of them continuing to grow 
nearly straight down. 

Typical lateral root stumps are elms, soft maples, locust, dogwood, elder, 
hemlock and some cypress. The roots of these trees grow in all directions from 
the trunk near the surface of the ground. Working the ground close about such 
stumps is next to impossible. 

The largest class of stumps is the semi-tap-root class. Belonging to this 
class are white pine, poplar, chestnut, ash, walnut, red, black, pin and other 
oaks, persimmon and sassafras. Stumps of this class are harder to remove 




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Wonderfully productive meadows, for timothy, alfalfa or other grass, can be made by cleaning up 
and draining stump flats. This land was a tangle of old logs and stumps a few months before the pic- 
ture was taken. (Michigan Land & Lumber Company.) 

than either of the other two types, because the roots generally are big and 
strong and grow in all directions, some along the surface, others almost straight 
down and still others between. 

What may be classed as a fourth division is composed of the root clusters 
of sprouts and bushes of almost any sort of trees, whose growth has not yet 
taken the characteristic form. Brush of willow, elder, maple, chestnut, hick- 
ory, oak and witchhazel may be named. The roots are very firmly anchored 
in the ground for a distance of three or four feet in all directions. 

The nature of the soil and the height of the water-table in it have much 
to do with determining the root growth. A hemlock tree, for instance, 
will send its roots down till they almost take on the nature of the semi-tap- 
root class in soil that is loose, free from stones and dry. The same tree would 
have few roots deeper in the ground than 6 inches where the soil is hard and 
the water-table near the surface. The root growth of other varieties of trees 



is affected by water and soil in the same way. A tree that grows on a steep 
hillside probably will have heavier roots on the sides than on the downhill 
and uphill grades. 




A glimpse of primeval forest and of primeval stumps, the like of which few farmers meet in 
the eastern part of the country any more. Such land is expensive to clear but it is exceptionaUy fertile 
in most cases. 



Some stumps are durable and others will rot very fast. White pme, 
Norway pine, locust and cedar stumps will last fifty years without 
decaying enough to make much difference in the work of their 
Rotting removal. Chestnut, white oak and catalpa are nearly as durable. 
The other oaks, poplar, ash, hemlock, hickory and gum rot so 
fast that in a few years a team of horses can roll out stumps of 
considerable size. 

It should be understood that during the first season, after any variety of 
tree is cut and the stump and roots die, the bark and soft outer layer of wood 
rots away, making the roots loose in their earth channels. It is the inner or 
mature wood which lasts. 

Another characteristic of stumps which is of importance in clearing plans 

is their sprouting. None of the pine stumps will sprout when 

a tree is cut, but nearly all the hardwood stumps will do so. 

Sprouting Chestnut is a great sprouter. A stump that does not sprout is 

not getting any worse as time passes, but one that does sprout 

is likely to be harder to take out each succeeding season. 

All kinds of stumps pull easier when the ground is wet than when dry. 

Explosives are more efficient in wet ground than in dry. Pulling 

machinery ordinarily is handicapped in very wet ground, because 

Water of the lack of firm footing. 

The nature of the soil, whether light or heavy, has a consider- 
able effect on the way stumps come out of the ground. Naturally 
a loose, fluffy sand will hold the roots less than heavy clay. Pulling them out 

10 



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This clump of trees was blasted out mot cut down.) The stumps are torn out better than 
they might have been without the weight of the tops to pull them over. 



of sand, therefore, is much easier than out of heavy soil. On the other hand, 
light soil will not confine the gases of explosives nearly as well as clay. In 
sand the greater ease of tearing the roots loose is more than 
Kinds of Soil offset by the lowered efficiency of the blast. 

The foregoing principles should be of more actual ser- 
vice to land clearers than a description of the conditions in different sections. 
If your stumps are Southern long-leaf pine, you know they will not sprout, 
and are of the tap-root class. If they are white pine of Michigan or Maine, you 
know they are of the semi-tap-root class, that they will not sprout and that they 



m^imAAi, 




This picture shows what they look like when down. The roots are torn out better than they would 
have been without the tops to pull them over. Note how easily they can be sawed or chopped. 

II 




When stumps are lifted by frost as much as some of these, they often can be pulled economically. 
They should be split up afterwards with light charges of explosive placed in auger holes or between 
roots, under a mudcap. 

probably will outlast you if you do not move them. In case of a locust stump 
in Oklahoma, you know that you have a lateral root stump to deal with, that 
will sprout and that will last as long as the white pine. These illustrations 
serve to point out how every reader can classify his own stumps as to facts 
about them that are important from the clearing standpoint. 



Methods of Clearing Land of Stumps 

A half-dozen methods of removing stumps are more or less well developed 
throughout the country. Everyone who clears land, whether it is only the re- 
moval of stumps from cultivated fields or the clearing up of logged-off areas, 
should study the different systems in order to decide which of them is best 
under any particular conditions. No one method is best all the time, and in 
nearly every case a combination of various means will be found most effective. 

Lists of Methods 

Digging out the stumps by hand. 

Pulling the stumps. The pulling may be done with horses or machines. 
The pull may be direct, or may be doubled or tripled in force by means of 
blocks and cable or rope. If with machines, it may be with a traction 
engine hauling direct, a donkey engine hauling by means of a drum and 
cable, a capstan puller run by horse power or man power, or a tripod 
puller which lifts the stumps straight up. (See pages 15 to 21.) 

Burning the stumps. The old-fashioned practice was to start a fire along- 
side a stump and keep it going till the stump was consumed. Charpit burn- 
ing consists of keeping an intensely hot but small fire about the base of a stump 
under a covering of earth. Another method is to bore auger holes through the 

12 



stump or part way through, to form draft holes and flues. A favorite method 
in some sections is to burn out the roots with a gasoline torch to a depth below 
the plow line. 

Finally, there is the use of explosives to blast out the stumps. 

Combinations of methods very often are valuable, and are recommended 
at proper points. 

Stump Disposal 

The land clearer must remember the necessity of disposing of stumps 
after they are out of the ground. It is expensive and difficult to haul or 
burn whole stumps. Several hundreds of pounds of earth nearly always stick 
to the roots of big stumps taken out unbroken. For this reason wherever it 
is possible to do so the stumps should be broken into pieces small enough to be 
handled easily before the job is considered done. There is no comparing the 
cost of burning stumps, when they have to be piled by means of a derrick, 
with the cost when they can be handled by hand. 



Choice of a Method 

Whether to remove stumps when they are green or to let them decay a 

year or more is a problem to be decided by your plans and the uses to which 

you will put the land. Newly cut-over land is clean. It has 

few weeds and no sprouts. In one season it will not develop 

Green vs. much of this growth, but in two or more seasons it will. 

Old Stumps and will be very much harder to clear than it would have 

been the first year. 

The stumps are hard to take out while they are green. 
It costs much more to do the work then than a year or more later, after the 
bark and sap-wood has rotted from the roots. 

But it costs money to miss crops, too, and if you are ready to put the 
ground to work at once, it is folly to wait for the stumps to rot. To wait from 
summer till the following spring is not a bad idea, for that loses little or no 
time, and starts the rotting process which makes removal easier and cheaper. 
Speaking in general of pulling and blasting, pulling the stumps probably 
is better and cheaper when the stumps are very small, and blasting when they 
are large. Where a large number of big stumps are to be removed a 
combination of the two methods is advisable. 

When stumps are small or numerous they can be pulled by a team of 

horses hitched direct, by a capstan puller, traction engine or donkey engine, 

with ease and speed. The pulled stumps can be handled by 

hand directly, and disposed of without trouble. The same 

Pulling and is true to a lesser degree when larger stumps grow small and 

Blasting shallow roots, which require but little power to lift and move. 

For stumps larger than 3 to 5 inches, explosives can 

be used alone effectively and economically, though there are 

important considerations which modify such a rule. One of them is that of 

soil. Explosives work more effectively in heavy, tight soil, such as moist clay, 

than in dry sand. Therefore, in dry, light soil it often is cheaper to pull all 

the stumps not too large to handle without breaking up, while in heavy soil it 

usually is cheaper to pull only very small stumps that will come out easily, 

and to use explosives, alone or in combination, for everything larger. 

13 



Old, well-decayed stumps too big to handle should be removed with ex- 
plosives alone. Small green stumps may be blasted out clean, roots and all, 
but large green stumps nearly always require a combination of methods, as. 




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This picture shows how the roots of large green stumps can be broken up for handlmg by proper 
blasting of the stumps. There is little reason in clearing a piece of land twice of the same stumps— 
once to free them from their beds and again to dispose of them— by pulling— when the job can be com- 
pleted with half the trouble and expense by blasting and hand piling. 

for instance, blasting and team pulling, or pulling with a capstan puller. The 
cost of explosives often can be cut down by making use of such a combination 
of methods. A heavy team, or other means of pulling, will take out roots 
after the ground has been loosened with explosives. 

Tap-root stumps larger than your arm should be blasted. Tap-root 
stumps cannot be pulled to advantage, though when very small they can be 
broken off by a side pull. Where land is swampy on the surface, and roots 
consequently lie shallow, a heavy team often can rip out stumps by direct 
pull, even up to fifteen inches in diameter. 

Large stumps that are pulled may be broken up afterward with small 
charges of explosives placed in auger holes, but in general it may be stated 
that large stumps should be blasted first. 

The folly of pulling out stumps that are big, and then spending as much 
money in getting rid of them as it costs to pull them, will be plain to any one. 
They can be disposed of at a fraction of the cost when they are well broken up. 
A more detailed consideration of the pulling of stumps probably is de- 
sirable. Pullers are most successful in the loose jack pine land of the North 
and the similar pine land in the South, and in clearing hardwood cut-over 
land where nearly all the stumps are small. They are 
particularly serviceable where the stumps stand close to- 
Capstan Puller gether, measure 3 to 6 inches and have root systems which 
do not bring up much dirt. Under such conditions a stump 
puller is a good investment, especially where there is plenty 
of man and horse labor available at low cost. 

But it does not pay to buy a machine for a small acreage of clearirig— 
only where a considerable quantity of clearing is to be done. In vicinities 
where the soil is light and there are many stumps on newly cut-over land, 

14 



several farmers should co-operate in the purchase of a stump puller and should 
help one another to use it. 

A stump puller works to least advantage under clay soil conditions. An- 
other factor is the water in the 




Two large hardwood trees which stood close 
together and were blasted out at one shot, without 
cutting down. About eight charges were used. The 
cavity in the ground is small and the soil is free from 
tight roots. 



ground. The ground must be fairly 
dry when the machine is used, even 
though the stumps require harder 
pulls then than when the ground 
is water-soaked. In mud, horses 
soon become mired deeply. Pull- 
ing of stumps must be done in the 
summer or fall. Of course, they 
cannot be pulled when the ground 
is frozen. 

A capstan puller can be used 

on a moderately steep hill, though 

the cost of pulling the stumps from 

such ground will be greater than 

from level land. Whenever it is 

desired to use a stump puller, have 

explosive materials on hand to 

blow out or to split and loosen any 

stump larger than about 5 inches. 

A donkey engine outfit especially designed for stump 

pulling can be used effectively and with success. It makes 

Donkey Engine an expensive outfit, however, and unless there are several 

hundred acres of clearing to do, consideration of it may be 

dropped. In the case of very large acreage, it is the logical 

form of capstan puller to use. 

A traction engine, pulling stumps direct, is a very effective means of get- 
ting stumps out. In fact, when such an engine is available it is doubtful if the 
purchase of any other machine ought to be considered. 
Both traction and donkey engine pulling is subject to the 
same limitations as pulling by any other means, and 
should be confined to such work as they can do to ad- 
vantage in comparison with explosives or other methods. 
The detailed consideration of the blasting of stumps may be short and to 
the point. The use of explosives reduces the labor of land clearing greatly. 
One or two men with explosives can do the work of a large crew with pullers 
or fire. 

The stumps can be blasted out clean. Thousands and thousands of acres 
of stump land are cleared completely every year with ex- 
plosives alone. While the use of some means of pulling 
in connection with explosives undoubtedly cuts down the 
cost on a large tract of clearing, the added ease and speed 
of the work of explosives alone is considered by many 
people to offset this economy. For small tracts or a few stumps it is foolish 
to provide pulling facilities. Do the work with explosives. 

The blasting splits the stumps into pieces easy to handle, and to sell or 
burn. When it is not desired to blast stumps out clean, the charges can be 
kept down and the stumps split and the dirt loosened and thrown away from 
the roots. The blasting does the work in a short time. 

15 



Traction Engine 



When to Blast 



The investment of money is 
kept down when explosives alone 
are used. There is no machinery or 
equipment left on your hands after 
the clearing is done. Yet the best 
use of stump pullers and of explo- 
sives is mainly distinct and differ- 
ent, and they should be considered, 
not in competition, but in combi- 
nation. A good team and a supply 
of explosive material is a winning 
combination nearly every time, and 
explosives are bound to play an 
important part in nearly every 
land-clearing operation. 

Digging out stumps is practi- 
cable under certain exceptional cir- 
cumstances. If you cannot get 
explosives and if you have men 
who are doing nothing, they may 
be put to digging out stumps; but 
if wages have to be paid, such 
clearing is bound to cost four or 
five times as much as when the 
work is done by better methods. 





.jf, *<*** 



*^ 



•^*. 




This pine stump is burning freely, and likely will 
be consumed if it receives some attention. The roots 
were bared of dirt and the stump was split by a 
light charge of explosive. When stumps can be 
left to dry for a couple of months after such splitting, 
they will bum very well, though pine stumps can be 
burned immediately afterward with a little coaxing. 



Big stumps such as this can be blasted 
Out electrically much easier and better than 
with charges fired with fuse. 



Burning by charpitting is a 
practicable and cheap method of 
getting rid of soft wood stumps of 
large size and in heavy or clay soil 
when the weather is dry for two 
months or more at a time. It is 
not successful in lighter soils. It is 
costly when labor must be hired 
for the purpose, and wastes time. 
This method of removing stumps 
is chiefly valuable for settlers of 
logged-off or cut-over land who 
must fight their way through with 
little or no money. 

Burning by 
means of auger 
When to Bum holes, and the 
use of oil, are 
freak methods 
not suitable for general use. They 
should not be attempted when 
the clearing operation is seriously 
intended to be economical. Burn- 
ing with a torch of some kind is 
effective, but expensive. 



16 



Detailed Directions for Clearing Land of Stumps 

Digging Out Stumps 
If you dig right down after the roots, trenching to bare them, cutting them 
off with an axe first at the sides and then underneath, the stumps can be 
rolled out as though they were pulled. The cost is high. 



•%#f^' 




Typical tap-root stumps, with the dirt washed away. To blast them out the charge must be 
located against the big root, four or five feet below the surface of the ground. Two charges to each root 
are better than one, though either loading will cut the root off successfully. 

If possible to know beforehand that you must dig stumps out, do it be- 
fore the trees are cut. Dig a trench about them, 
taking away the support, and cut the lateral roots. 

Trench about Trees and then let the wind and water finish the job. The 
water in the trench will soften the subsoil. The best 
time of year to do it is in the spring, when the wind 

is strong and the ground is loose. 

Burning Out Stumps 

Charpitting is perhaps the best method of burning stumps. The fire is 

kept burning at the base of the stump till it burns entirely through, and till 

the top is consumed as it settles down and the roots are eaten 

out to a proper depth below the surface of the ground. The 

Charpitting fire is confined by a covering of earth. 

Charpitting is effective only when heavy grounds can be 
secured to cover the lire. Sand, loam or other light soil cannot 
be used for the purpose successfully. 

The stumps should be reasonably dry, and the weather should be dry 
during the burning process, which takes two to six weeks. Light showers are 
not objectionable, but heavy, settled rains cause failure. Pine stumps burn 
best, because of the pitchy nature of the sap remaining. Any 
other soft wood can be burned this way. The successful burn- 
Conditions ing out of hardwoods requires favorable conditions in all re- 
spects, and is rather doubtful in the hands of inexperienced 
operators. 

17 



The procedure is as follows: Remove the bark from the base at least. 
On some stumps it is necessary to dig away a little dirt. The fire should be 
started low enough so that it will burn in under the stump at the spaces be- 
tween the roots. 

Gather some fuel wood — any kind that will make good 

coals, though mixed oak and a little pine likely will be best. 

Directions Cut this wood like stove wood — say about a foot long, and split 

fairly fine. Lay and stand the sticks round the stump till you 

have a layer at least 6 or 8 inches thick. You can pile wood 

and start the fire entirely round the stump, or only about a quarter of the 

way round as you prefer. Putting wood all round takes more wood 

and more time to prepare, but burns the stump out quicker and has more 

chance of success. 

After the wood is in place it must be covered with a little straw, fern or 
other material of the kind, and then with a thin layer of dirt. The dirt layer 
should not be more than 3 or 4 inches thick. It must be of clay or very heavy 
soil. The dirt should be piled against the stump up to about 18 inches high, 
but no higher. 

Start the fire at each quarter of the space round the stump. That is, if 
the wood runs only a quarter way round, start one fire; if all the way round, 
start 4 fires. Leave the holes where the fire is started open only for a little 
while, and then cover them up. 

The fire must be kept covered all the time and never be allowed to burn 
into an open blaze. It is really smouldering and coaling of the wood. When 
the fire blazes much of the fuel supplied is burned up and the heat is lost in- 
stead of forced to eat its way into the stump. The object is to confine 
the heat. When this is properly done the fire becomes intensely hot round 
the stump. 

As the stump burns through and the fire goes deeper, the dirt cover may 
break through. Such places must be covered with more dirt. If the fire burns 
higher up the stump than where the dirt is piled in the first place, put it out 
up there instead of trying to pile the dirt higher. 

As soon as the stump is burned through, the top will settle down and con- 
tinue to burn. Keep the fire covered over the ends of roots that burn off, so 
it will eat its way deep into the ground. If it breaks out to the air it will not 
burn far. While the stumps are burning they must be watched and visited 
several times a day. 

The cost of charpitting in the manner described is high when the actual 
time of the operator must be accounted for at regular rates of wages. 

Another good method of burning that really is charpitting of a modified 
form, is to saw the stumps off close to the ground, block up the top part, and 
to start a fire between the two sawed faces. The faces 
should be as close together as possible while allowing 
Idaho Charpitting the fire to be started and to burn. Bank up the out- 
side with dirt, as directed in preceding paragraphs, and 
keep the fire covered till the stump, roots and al). is 
consumed. Use stones to hold the two parts of the stump apart. It is best 
to do the sawing in the winter and raise the top part then, leaving it to dry 
out several months. The burning is done best in the summer. 

18 



Burning with a torch is simply a matter of digging away the ground from 
the roots, and applying the intensely hot flame at a point 
below the plow line. Torch burning is expensive business 

Torch Burning when time and fuel costs are counted up. The best kind 
of a torch to use is one with a fan or bellows. The kind 

of fuel used by the torch is not important, except that some fuels burn 

better than others. Gasoline perhaps is best. 

A modification of charpitting sometimes is advisable in the case of pastur- 
ing the land for several years. The stumps are split and their roots un- 
covered with small charges of explosives. When they 
are thoroly dry, wood is piled between and over the split 
Plain Burning tops of the stumps and the whole thing is set on fire. 
With a little attention to keeping the burning ends of the 
roots covered with ashes and dirt toward the last, stumps 
may be consumed entirely by this method. It is not nearly so much trouble 
as charpitting, because the fire burns fiercely in the dry, shattered tops, and 
needs no attention other than the first piling of the fuel till it is time to look 
after the burning out of roots. 

Pulling Out Stumps 

Four forms of pulling are worth considering. These are by horses direct, 
with hand pullers and capstan pullers, and with donkey engines and traction 
engines. 

A good heavy team of steady horses will take out most of the stumps which 
should be pulled whole, and almost any roots left by proper 
use of explosives where blasting and pulling are used in 
Four Forms combination. You will need a couple of good log chains 
of Pulling and a regular outfit of singletrees and spreaders. To in- 

crease the strength of the direct pull, you can use a 
frame made of 6 by 6 pine pieces in the shape of the letter 
A. Make it 6 feet high. Attach a short piece of chain round the tip of the A, 
to run down to the roots over the top of the stump, or else run the main chain 
from the horses over the top of this frame before attaching to the stump. Such 
a haul will upset a stump much easier than a direct hitch. 

If you have to pull without the frame, aim to pass the chain over the top 
of the stump and hitch to a root on the other side, the farther out the better. 
Another good hitch and haul is the twist. Hitch to a root and drive so that the 
chain tends to wrap round the stump. 

When saplings are to be removed do not cut them first, but 
hitch the chain to them as far up as you can reach. While the team 
is hauling on them, a man should cut the roots on the opposite side with 
an axe. 

A few days of stump pulling is enough at one time. Rest the 
horses and men at some other work. The clearing of land by this method 
is heavy and tiresome, and can easily become disheartening if kept up 
too long. 

A capstan puller consists of a frame, a drum on bearings, a pole to hitch 
horses to, and a wire cable fastened to the drum. Some of them have gearing 
which reduces the speed of the drum and increases its pulling power. These 
work very slowly. 

19 



The pullers have to be anchored to solid stumps near the place where 
they are set up. The limiting factor in the use of pullers 
is this anchor or anchors. When you pull, you do not 

Capstan Pullers always know whether the stump out at the end of the 
cable or the one behind the machine will come. To set 
the machine takes time, and you should be careful to 

make the anchorage as secure as possible. 

If your puller comes without a pole, you can get one in the woods near 
home. Cut a 6-inch tree — ash, white oak, hickory or the like — and use a 
20-foot length. Better attach an old wagon tongue to this where the horses 
are to be hitched, to keep the pole from hitting the horses when stumps give 
way suddenly. Some operators also attach a second pole in front of the horses, 
to lead them in the circle, saving continued driving. 

It is better to wind up the cable on an empty drum; the cable 
wears much less in this way. For that reason use only enough cable to 
cover the drum — not two layers on it. The length of the cable will govern 
the area you can clear with one set of the machines. This usually will be 
about an acre. 

Three men can clear an average acre of cut-over land of small stumps in 

one day. Three men will handle a small outfit. Handling the cable is heavy 

work, and you want no boys on the job. The hooks for catching the roots 

that come with the machines usually are poorly designed. You can have a 

better one made by welding together two old steel plowshares in a manner 

that your blacksmith will understand if you show him the 

original hook. For best results a hook should weigh about 

Time to Pull 50 pounds, though to be so light it must contain only good 

steel. 

Pullers are not suited for taking out occasional stumps in 
cultivated fields, but only to clearing cut-over land where stumps stand close 
together. The machine should be brought on the job only after the necessary 
blasting has been done. Then the small stumps and whatever roots are left 
by the blasting can be taken out at the same time. A supply of explosives 
should be kept on hand for blasting out the anchor stumps after the machine 
has done all the work it can. 

A tripod puller is effective, but cumbersome to handle and expensive to 
operate. It is not recommended. 

A donkey engine for stump pulling should have about the same 
power as for logging operations, and should be constructed about the 
same. There should be two drums, one for the pulling cable and the 
other for the return line, the return drum geared faster than on a logging 
donkey. 

About 350 feet of pulling cable can be used. Inch or inch and a quarter 

cable usually will be best. The return line would be 

Donkey Engine half or five-eighths inch. With 350 feet of main cable, 

Outfit 10 acres can be cleared at one setting. It speeds up 

operations to use a cluster cable with three or four 

hooks. Several small stumps can be pulled at once with this. 

A donkey engine outfit requires five or six men to operate it. With it 
stumps of any size can be pulled. When they are too big to handle directly 

20 



Traction Engine 
Pulling 



it is best to break them up with explosives before attempting to burn or other- 
wise dispose of them. Very large stumps should be loosened and split before 
they are pulled. 

Little needs to be said about using a traction engine. You will need heavy 
chains and heavy hooks. The chain should be nothing less than five-eighths 
inch. A short piece of inch or larger wire cable is better. 
Fifty feet or so is enough. The hook should be of steel, 
with one point, and should weigh 50 to 1 00 pounds. The 
entire hitching apparatus should be strong enough to 
stand jerking on with the weight and power of the 
engine. 

The cost of operating pulling machines and of clearing land with them 
varies so much that no figures are safe to depend on. It depends on 
the kind of soil, the kind of stumps and especially on the skill with 

Cost which the machines are operated. When everything is at the very 
best, land can be cleared economically with donkey engines and trac- 
tion engines in combination with explosives. When conditions are 

not favorable the cost of these methods is very high. 

For any kind of stump pulling you will need shovels, hoes, axes 
Tools and bars. The probing rod also is useful for locating roots. 

The directions for removing stumps with explo- 

Blasting Out Stumps sives are given in full detail, and in order to do the 

matter justice they are placed in a separate chapter. 



Blasting Out Stumps 

A proper charge of explosives placed under a stump will tear the roots loose, 
lift the whole stump out, and break it into pieces. The whole operation is 

simple, safe, short and easy. Any 
sort of stump, of any size, in any 
soil, any weather, can be blasted 
out successfully, and the blasting 
is a practical and efficient method 
whether there is one stump to be 
removed from the middle of a cul- 
tivated field or a lawn, or thousands 
of acres of the heaviest logged-off 
land clearing to be done. 

The best time of the year to 
blast out stumps is a matter of 
compromise between conflicting 
requirements. On the one hand 
explosives work most effectively in 
moist clay and wet sand soils. On 
the other hand, it is bad from a 
tillage standpoint to blast heavy 
ground when wet. (See page 38 
for further discussion.) 

With all the facts before you, the selection of time is a matter for your 
own judgment. If cost did not need to be considered, summer or fall would 

21 




It is folly to attempt to blast out many big 
stumps, such as this one, without an electric blast- 
ing machine. Such a stump should have six to eight 
charges properly located about it. These numerous 
charges will contain less total explosive than one 
charge large enough to remove the stump. The hole 
they make is much smaller. 



be ideal. Blasting out stumps from frozen ground can be 
done with satisfaction. In fact, the stumps are broken up 
Time or Year better then than at any other time, though the work is 
harder on account of the difficulty of making holes. 

Success, and especially economy, in stump blasting, is a matter of common 
sense and judgment plus some knowledge of the stumps and of explosives. 
Close attention to apparently small matters insures good work. The things 
that the blaster must consider are the location for the charges, the proper size 
of holes, the amount of explosives required, the length of fuse, depth of hole, 
tamping and the like. 

Loading Charges of Explosive 

To blast out a stump the explosives must be placed in a hole underneath 
it. Make the hole first. Then prepare the charge of explosives as directed 
on pages 34 to 38. Pack the explosives in the hole, tamp and fire. 




In blasting out big green stumps, the holes for the three to eight charges should be made as nearly 
as possible under the main anchor roots. The man on the right is smoothing out a hole, getting it ready 
for the charge; the one on the lelt is shoving a stick home with the tamping rod. 



Depth for Charges 



Load stumps by no rule, but with regard to their root systems and to the 
nature of the soil. The aim is to tear the roots out of their anchorage in the 
ground, or to break them off below tillage depth. To do this you must place 
the charge or charges of explosives as close to their 
burden as possible — hitch them as short as possible to 
the load. The load or burden is not the weight of the 
stump so much as its grip on the ground. You must 
get good confinement of the gases. If there is a weak 
wall on one side of an explosion and a fairly solid or firm wall on the other, the 
weak wall will give way, and very little breakage or movement will be made 
in the other. 

The charge of explosives should be located just deep enough to secure this 
confinement and to be under the load to be lifted, but not any deeper. If 

22 




charges are too deep there is great waste of energy in uselessly lifting earth. 
This is costly. Charges that are placed too shallow will blow off the tops of 
stumps or split them, leaving roots tight in the ground. 

Since clay and other heavy 
soils hold the gases much better 
than sand, and wet ground holds 
them better than dry ground, a 
much thicker covering of dry sand 
is required over a charge to confine 
the gases properly than of wet 
clay. Charges, therefore, must be 
placed deeper in sand. Usually the 
charges should be placed right next 
to the wood of the roots in clay 
soil, and in sand with 6 to 30 inches 
of ground between the charge and 
the roots (tap roots excepted — see 
next page). Large stumps, and old 
stumps, require shallower placing 
of charges in proportion to diam- 
eter than small stumps and green 
stumps. Long-rooted stumps re- 
quire deeper placing than short- 
rooted ones. 

With the foregoing points in 
mind, it will be seen that the 
charges should be placed directly 
under that part of the stump that 
will give the greatest resistance. 
This may be the center, but it is by no means always so. If the stumps 
have grown on a hillside, the roots may be heavier cut sideways than 
uphill or downhill. Very often a tree on the level has heavier roots on one 
side than on the other. Usually it is of advantage to blast a big stump 
with more than one charge, placing one charge under each of the large roots 
and one under the center of the stump. A charge under a root should be at 
a point where the weight of the stump will be balanced by the pull of 
the ground at the other end. This point usually will be a foot or two out from 
the edge of the body of the stump. 

In the foregoing suggestions, no mention has been made of the three main 
types of root growth — tap-root, semi-tap root and lateral root; but with the 
principles of blasting in mind, it is easy to see that a properly placed charge 
under a lateral root stump will be very shallow. If such a stump is to be taken 
out with several charges instead of only one, all but one of the charges will 
have to be located well out from the stumps proper, under main roots. 

Semi-tap root stumps require deeper placing of charges than lateral root 
stumps. When such stumps are taken out with more than one charge, the 
points for the explosive are closer in, under the main roots where they dip a 
couple of feet below the surface. 

The underground nature of each stump should be determined before plac- 
ing charge or even making holes. You can do this partly by observing the roots 
that rise above the surface, but mostly by probing down among the roots with 

23 



The charges are placed and the wires connected, 
the stock has been chased away and the helpers 
warned back — now the blaster is ready to shove the 
handle of his machine down and to fire the explosive. 




How cartridges of powder swell and fill the hole 
when they are split and pressed with tamping stick. 



the quarter-inch steel needle known as a probing rod. Every blaster should 
have one of these rods and should make use of it at each stump. 

There are two ways of blasting 
out true tap-root stumps. One is 
to bore a hole in the wood of the 
tap-root itself, and the other is to 
place the charges right alongside 
the root and against it, like mudcap 
charges are placed in stone blasting. 
In placing the charge in the wood, 
make a hole in the ground down to 
a point a couple of feet below the 
surface of the ground. Then bore 
a hole in the wood with a wood 
auger. This hole should go two- 
thirds or three-fourths of the way 
through the root. Fill the hole in 
the wood with explosives, fire, and 
the resulting blast will cut off the 
root. 

In placing the charge of explo- 
sives against the wood, get it at 
least 4 feet deep. If you can com- 
mand an electric blasting machine 

for firing, divide the charge in two and place the two parts on opposite sides. 
These charges may be placed only 'i\<2 f^^t deep, though you should not hesi- 
tate to place the charges at a greater depth when blasting large tap-root 

stumps, particularly if the ground 
is of a light nature. 

In all sorts of stump blasting 
the holes for the charges can be 
dug with narrow-bladed shovels, 
spades or crowbars, or bored with 
dirt augers. (See page 32.) In 
stony land augers cannot be used, 
or can be used only for parts of 
the holes. All 
things consid- 
Making Holes ered, it is hard 
to beat the bar 
and sledge com- 
bination for making holes for 
charges of no more than two or 
three sticks, or for starting holes 
for larger charges. 

The bored hole is better than 
the dug one because it can be 
tamped tighter. After much dirt 
once is taken out, it will not be 
tamped back in again as solid as it 
was before. Holes for inch-and-a- 
quarter sticks of explosives should 




How to place charges for blasting out tap-rooted 
stump. Three methods are shown. "A" shows how 
to do it with one charge, using cap and fuse and not 
boring into the wood. "B" shows how to place two 
charges when electric blasting machine is available. 
"C" shows by dotted lines position of auger hole in 
wood where one charge could be placed to cut off 
the root and throw out the stump. Any one of the 
three methods will do the work. 

24 



be made with inch-and-a-half augers or bars. In blasting exceptionally large 
stumps, use 2-inch or 3-inch augers. The holes usually can be started between 
roots and in depressions, but do not sacrifice good placing of charges for ease 
in making holes. 




How to place charges under lateral rooted stump. "A" shows how to place charge when the cap 
and fuse are used and one charge is relied upon to remove the stump. "B" shows how to place 
three small charges under main roots when stump is to be removed with several charges fired by electric 
blasting machine. Use either method "A" or " B "^ never both . 

In water-saturated ground of a heavy nature, in case you have difficulty 
in getting the charge properly centered or placed (when no electric blasting 
machine is available for firing), you can make use of what is known as propa- 
gated detonation. Divide the big charge into several small ones in different 
holes bored from two, three or four sides of the stump, but all ending close 
together down under at the right point. If these charges are tamped solid and 
they are not more than a foot apart they all will explode at once when one of 
them is fired with a cap and fuse in the usual way. 

In making holes for blasting out tap-root stumps, start the bar or auger 
straight down along the root from the surface. When you have reached the 
required depth, wriggle the bar sideways to make the hole wide at the bottom. 

Wherever the number of stumps runs into many thousands, it will pay to 
get a machine to bore the holes. Such a machine will bore all the holes needed 




I How to place the charges under semi-tap-rooted stumps. "A" shows proper position where one 
charge and cap and fuse are used. "B" shows proper positions of several small charges when electric 
blasting machine is used. Use either one or the other method illustrated — never both. 

25 



under the stumps at the rate of 500 or 600 a day, and at very much lower cost 

than the same work can be done by hand. The machine 

bores almost as fast in wood as in earth, and is particularly 

Power Boring serviceable when roots have to be penetrated in order to 

get the charges to the right spots. 

Machines can be bought complete in small sizes suited 
to land-clearing purposes, or can be bought in parts and assembled on home- 
made frames. Electric machines are most convenient. Steam and compressed 
air machines are next best. Flexible shaft machines and direct-geared machines 
are least satisfactory. The flexible shafts break. The steam outfits freeze up 
and are troubled with burst pipes. All the outfits except steam ones can be 
run by gasoline engines. 







To show sticks of explosives expanded, as permitted by splitting of stick wrappings, in big hole. 

An electric boring outfit consists of a small gasoline engine — say about 5 
horse power — on a wagon belted or geared to a 3 kilowatt dynamo, and that 
equipped with two drill heads and 200 feet of electric cable. A supply of l}^- 
inch augers completes the outfit. Such an outfit costs about $500. You can 
use any gas engine. The dynamo will cost somewhat less than $250, and the 
drills about $80 each. 

It takes five men to run this outfit — two men on each drill and one man 
to drive and to handle the cables. This man should lift the cables carefully 
over stumps and prevent them from kinking and getting caught. The steam 
and compressed air and the direct drive machines will not be described, be- 
cause improvements continually are coming out. Watch the farm papers for 
advertisements, or write to any maker of explosives for names of manufacturers 
of these machines, if you are interested in them. 



26 



Study the methods of handling explosives as outlined on pages 34 to 40 
and 58 to 61, to which every reader is referred at this point, before trying to 
load charges. A few special hints will be given here. 

Charges of explosives usually should be as near as may be in a round bulk — 

not strung out for 2 or 3 feet in a long hole. To get them so the hole must be 

enlarged at the bottom by scraping or springing. Slit the paper 

wrappings of the sticks and press the sticks in the hole with 

Slit Stick the tamping stick till they swell to fit the hole tight and shorten 

Wrappings to 2 to 4 inches in length. (See pages 24 to 26.) But do not 

do this if the hole is very wet. 

When you have many stumps to blast out, it often is a 
good practice to make holes in the forenoon and then to load and shoot after 
dinner. Load and fire all the holes you have prepared when you go to the 
field, after which you can proceed to make more holes. Always fire the charges 
soon after they are loaded. To do this prevents missing charges, and avoids 
chance explosions due to meddling, and the like. If the holes are wet, firing 
immediately is required to avoid weakening of the explosive by water. 

If you prepare your charges in the field, you can cut a supply of pieces 
of fuse before you go out. Make the pieces of varying lengths and crimp caps 
on them to prevent the powder shaking out of the ends. Take the roll along 
with you to provide for holes requiring longer fuse. Don't attempt to use 
pieces of fuse less than 15 inches long. They are dangerous. 

Use plenty of water when tamping the holes, and tamp well. See that 
the ground is packed solid, not only where you made the hole, but all around 
the stump. Often there are holes dug by skunks, groundhogs, gophers, squir- 
rels, rats or mice under stumps. 
Keep the charge of explosives away 
from these cavities — better fill them 
up. 

In lighting many fuses a gas- 
oline or oil torch is useful. But 
there isn't anything much better 
than to stick the burning end of a 
freshly scratched match right 
against the powder in the end of 
the fuse. (See page 58.) Remem- 
ber that the outside cover of the 
fuse does not burn, but the spark 
runs down the center as a drop of 
water might run down a tube. Do 
not leave the fuse till it spits sparks 
regularly. 

None of your charges are likely 
to misfire if you load carefully, and 
if you have taken proper care of 
your explosive materials before 
loading. But if misfires do occur 
with fuse, do not investigate them 

Some such appearance is necessary in stump r c*.i7f>ral Knnrc at Uacf ^Saa 

blasting, but the less of it there is the better. The ror several nours, at least. <,Oee 

ideal blast is just strong enough, and is so located, p^ae 63 for disCUSsion of misfires.) 

that it rolls the roots free of their beds and splits ^ ° ^, . ■ 

them apart, but does not throw them an unnecessary Ul COUrse, in elec- 

foot. Loud reports and much dirt high in the air TV/Ticfirfic trir firi'na vnii ran 

show careless loading and useless expense. iVilfalireb trie nring you can 




27 



investigate a misfire immediately after the wires have been disconnected at 
the blasting machine. 

Amount of Explosives Required to Blast Out Stumps 

A proper charge of explosives for a stump blast has a dead, muffled report. 
It lifts out and splits the stump. Loud report and the throwing of the pieces 
far shows that too much explosives have been used. When stumps merely are 
split and tight roots are left, not enough explosives have been used (or it may 
be placed too shallow). If the explosion is muffled and does not throw pieces 
far, but digs too big a hole, the charge is too heavy and too deeply placed. 

It is impossible to lay down exact rules for the amounts of explosives to use. 
This bulletin will include figures of amounts that have been used to blast out 
some stumps, but these figures must be regarded as correct only under identi- 
cal conditions of soil, kind and age and size of stump, amount of water in soil, 
kind and grade of explosives, and amount of confinement in the hole. Experi- 
ence must be the teacher in this matter. 

A green stump requires a great deal more explosive than one that has 
stood a few years. More explosives are required in stony land than in smooth 
land to blast out stumps. The harder and heavier the soil is, the less explosives 
are required, and the looser and lighter it is the more explosives are required. 
Dry soil requires more explosives than moist soil. 




?»i* ^ 



•i- jsrfWi'v*^ • 




''•^i^m>f'. 



As these roots lie, they show the result of an almost ideal blast. There is little hole in the ground; 
the stump is well broken up; the roots are cleaned of dirt; and no roots have been thrown very far. 

When you want to blast a stump entirely out, it is better to load 
too heavily than too lightly, for roots left tight in the ground after the top of 
a stump is blasted off are hard to get out. If you are not familiar with stump 
blasting, start with the small stumps and load them as you think they should 
be after considering the various points explained in foregoing pages, and in 
view of the following figures. 

Ordinarily it takes one pound of explosives for each foot in diameter of 
stump, when the stump is such as a white pine in clay soil cut 10 years 
or longer. Green stumps of any kind require more than this — usually about 
half again as much; sometimes twice as much. A rule for the enormous stumps 

28 



of the Pacific Coast is to square the diameter of the stump, measured in feet, 
and use this figure as the number of 13^ by 8 inch sticks of explosives required. 
This rule usually over-estimates the amount required for stumps larger than 
3 feet in diameter. 





Examples of the incomplete job resulting from trying to blast out very big stumps having wide- 
spreading roots, with one charge to each one. Unless the charge is excessively heavy, which means 
that it is expensive in explosives and in loading, it can not be placed deep enough to remove the whole 
stump. Even if it is deep enough and heavy enough to be successful it is objectionable on account of 
the big crater made. Each big stump should have several charges. 



Amount of Explosives Used to Blast Stumps 

The following table is taken from records of blasting in Minnesota, Penn- 
sylvania, Oregon, Kentucky, Michigan and Florida. The stumps were blown 
out effectively and successfully, and the figures should serve as a reliable guide. 



Diameter Stump 


Kind 


Inches 


Stump 


10 


Pine, dead 


12 


Pine, dead 


12 


Pine, dead 


12 


Pine, dead 


14 


Pine, dead 


15 


Pine, green 


16 


Pine, dead 


18 


Pine, dead 


18 


Pine, dead 


18 


Pine, dead 


20 


Pine, dead 


20 


Pine, dead 


24 


Pine, dead 


24 


Pine, green 


24 


Pine, dead 


24 


Pine, dead 


24 


Pine, dead 


36 


Pine, dead 


36 


Pine, dead 


36 


Pine, dead 


40 


Pine, dead 


48 


Pine, dead 


48 


Pine, dead 



Kind 
Soil 


Sticks IJ-I inch 
Dynamite or Powder 


Clay 


1 


Sand 


13^ 


Loam 


1 


Clay 


1 


Clay 


2 


Loam 


4 


Clay 


^A 


Sand 


3 


Loam 


2 


Clay 


IH 


Sand 


7 


Clay 


4 


Loam 


5 


Sand 


10 


Sand 


53/2 


Loam 


43^ 


Clay 


4 


Sand 


10 


Loam 


8M 


Clay 


73^ 


Clay 


7 


Sand 


13 


Loam 


10. 



29 



Diameter Stump 
Inches 

48 
60 



12 
12 
15 
16 
16 
18 
20 
24 
26 
27 
27 
30 
30 
34 
38 
30 
36 
40 
48 
72 
60 
15 
10 
15 
24 
16 
16 
20 
6 
8 
10 
12 
15 
18 
6 
8 
12 
15 
18 



Kind 
Stump 

Pine, dead 

Pine, dead 

Oak, dead 

Oak, dead 

Oak, dead 

Oak, dead 

Oak, dead 

Oak, green 

Oak, dead 

Oak, dead 

Oak, dead 

Oak, dead 

Oak, dead 

Oak, dead 

Oak, dead 

Oak, dead 

Oak, dead 

Oak, dead 

Fir, dead 

Fir, dead 

Fir, green 

Fir, dead 

-Fir, dead 

Spruce, green 

Hemlock, dead 

Walnut, dead 

Gum, green 

Gum, dead 

Black gum, green 

Sugar maple, green 

Snag, dead 

Tap-root pine 

Tap-root pine 

Tap-root pine 

Tap-root pine 

Tap-root pine 

Tap-root pine 

Tap-root pine 

Tap-root pine 

Tap-root pine 

Tap-root pine 

Tap-root pine 



Kind 
Soil 


Sticks \}4 inch 
DsTiamite or Powder 


Clay 


9 


Clay 


15 


Sand 


IH 


Sand 


2 


Loam 


13^ 


Loam 


\y2 


Clay 


1^ 


Clay 


3 


Loam 


3 


Loam 


3^ 


Clay 


3 


Clay 


2 


Sand 


5 


Loam 


43^ 


Clay 


4^ 


Sand 


6 


Clay 


43^ 


Clay 


5K2 


Loam 


10 


Clay 


12 


Loam 


20 


Loam 


26 


Clay 


36 


Sand 


32 


Sand 


2 


Loam 


1 


Clay 


M 


Sand 


4 


Sand 


5J^ 


Sand 


5H 


Sand 


43^ 


Sand 


V2] 




Sand 
Sand 


1 


Charge 


Sand 


13^ 


" m 
wood 


Sand 


2 




Sand 


2MJ 




Sand 


1 1 




Sand 


13^ 


Charge 


Sand 


3 


against 


Sand 


4 


wood 


Sand 


5 





Proper blasts throw out little dirt. They pull the roots out of the ground, 
and permit most of what little dirt they do lift to fall back in the hole. In 
consequence good blasting leaves small holes. 

An excellent plan for any blaster is to carry a notebook and a yardstick 
and keep track of the blasts he makes. Make note of the size, kind, age of 
stump, kind of soil, amount of water, kind and amount of explosives used, and 
the result of the blast, in each case. 

30 



The figures here given will serve as a guide for the first shots, 
work proceeds, base your loading on your own experience. 



As the 



^^..si^fer ■ 




>5f -^- 



Here two charges, fired together electrically, were correctly proportioned and placed except that 
one was located too shallow and too far in toward the center. It should have been out under this re- 
maining root, shown in the picture, which then would not have required pulling with horses or another 
blast. 

Kind of Explosives to Use 
The kinds and grades of explosives best to use for blasting out stumps are 



few, and vary with the nature of the soil. 




The single charge under this stump was placed 
too deep and too much to one side. It exhausted 
most of its energy in the ground far below the roots, 
and then what was left escaped between the roots, 
blowing the dirt away but not having enough power 
to carry the roots with it. 

31 



In a heavy soil an explosive which 
cracks, lifts and heaves is more 
desirable than one which shatters. 
In other words, a slow-acting ex- 
plosive is the one to use. This 
means dynamite or powder of 20% 
strength or less; and further, in dry 
work or where the charges can be 
fired quickly after loading, it means 
ammonia explosives. If the charges 
must be exposed for some time to 
water, nitroglycerin powder or 
dynamite had better be used. 

In dry, light soils, such as dry 
sand, it is necessary to use an ex- 
plosive that exerts its full force 
before the gases can give way, as 
in mudcapping rock. For that 
reason 50 'f, ammonia or nitro- 
glycerin powder or dynamite is the 
explosive to use in dry sand and 
similar soils, or 60% will do. Inter- 
mediate grades of soil usually can 
be depended on to hold the gases 
enough to permit the use of the 
slower 20% explosives. 

The above does not mean that 



these grades of explosives are demanded for removing stumps. The fact is 
that stumps can be blasted out with almost any explosives manufactured; but 
the work can be done more economically and cheaply if the grades recom- 
mended above are used. 




Four charges fired together tore this stump loose from its moorings and moved it six feet down the 
hill, but did not break it up. Another charge should have been located close under the center. It can 
be broken up easily now, however, by loading one stick charge down in the center of the hollow top. 
THIS STUMP IS A WHITE PINE, CUT 75 YEARS AGO. 

The 20% explosives, especially the ammonia, leave the ground in better 
condition. A violent and quick-acting explosive tears out large holes in heavy 
ground, and packs the earth about the edges. 

Time Required for and Cost of Blasting Stumps 
A day's work for one man is 30 to 60 average stumps blasted out. If 

three men can work as a crew, two making holes and one loading and firing, 

the number of stumps per man will be much increased. 

The cost of blasting stumps is a variable quantity. Those which blast 

out the cheapest are well-rotted oak or walnut, in moist clay soil. Probably 

the stumps which cost most to blast are green white pine or oak in dry sand. 

The skill and good judgment of the blaster also has much to do with the cost. 

Tools 
The tools you will need for blasting stumps are all common ones. The 
pictures show better what they are like than words can tell. You can use 
grubbing hoes, axes, crowbars for driving and for hand use, soil augers, long- 
shanked wood augers, wood tamping sticks, cap crimpers, water buckets, pocket 




3 11 



32 



knives, steel probing rods, adzes, 
long-handled shovels, spade shovels, 
spoon shovels, scrapers, spoon bars, 
sledges and possibly other tools. 

An old wood auger does not 
make a good soil auger, though it 
can be used in a pinch. For boring 
in ground an auger should have a 
leading point 2 or 3 inches long. 
Both wood and soil augers should 
have cutting bits that can be filed 
sharp a good many times without 
destroying them. Most blasting 
tools are supplied by all makers of 
explosives, and by hardware dealers. 
Some of them can be made at home, 
by your blacksmith. 

The spoon shovel and spoon 
bars are for tunneling and enlarging 
bore holes. Make them by turning 
up and trimming the edges of long- 
handled shovels. The probing rod 
is a piece of quarter-inch steel 6 
feet long, with one end sharpened 
to a point. It had better have a 
handle turned over, or made into a 
ring. No long description of any of 
these tools will be given here, because 
farmers are familiar with them. 
This bulletin recommends electric firing for stump blasting strongly when- 
ever there is enough blasting to be done to justify the purchase of a blasting 




This stump came out as a result of a charge that 
was placed too deep and a little to one side of the 
proper position, and is not broken up for handling. 
It can be broken very easily as it lays, by locating 
a one stick mudcap charge between the two large 
roots seen in the picture. Had the original charge 
been a foot nearer the surface, the stump would have 
been broken in several pieces and all thrown out. 




A very old white pine stump blown out with three charges fired together electrically. The stump 
is well torn loose and cleaned, but another charge should have been placed at a point close to the wood 
under the center, to spUt the stump for easy handling. 

33 



machine. (See page 63.) One to fire up to 10 charges can be obtained at a 
moderate cost. If skillfully handled its use will save its cost for each 500 
pounds of explosive fired. Electric firing makes possible work in stump blast- 
ing that is superior to the work produced by any fuse firing when conditions 
are difficult. The several small explosions help one another. 




The blaster located his charges under this stump too far toward one side. The result is that the roots 
of the other side are left sticking in the ground and require another blast. 

General Hints 

To blast out standing trees, use about twenty per cent, more explosives 
than you would for the stumps. It is better to blast big trees with several 
charges, firing them electrically. 

When big green stumps are blasted out with one charge placed under the 




The result of an attempt to blast out a very large green stump with one charge. The explosives 
were located deep under the center, but they could not reach out far enough to tear loose the many firmly 
anchored roots. They blew off the top, instead. Such stumps should be blasted with three or more charges 
all fired together electrically. 

34 



center, some of the roots often break off high up, so that they interfere with 
plows. They are better blasted with several charges placed round the edges. 
If you are using a stump puller, split and loosen all the big stumps with ex- 
plosives before pulling them. 

It is more expensive to remove severely burned stumps than those with 
the tops intact. In blasting decayed stumps and those with no tops, fill the 
center cavity with ground and tamp it tight. Then place the charges in the 
usual way. 

In blasting old rotten stumps that have sound roots, you often find the 
center underneath has rotted out, or become so that it is only a mass of punk. 
This material will not hold the gases of the explosives. To blast such stumps, 
better use an electric blasting machine, and several charges, or if fuse must 
be used, place the charges under the roots, or deep under the center, filling 
the hollow center with wet clay or loam. 

Old logs and snags frequently are too big to haul or handle and to burn 
on clearings. Do not waste time cutting them in two, but smash them up 
with charges of about half a stick of explosives placed in an auger hole. If no 
auger is handy, put a heavier charge in a notch chopped in the log and cover 
with 6 inches of mud. 

Fat pine tap-root stumps often may be shattered by charges of explosives 
placed in the top-roots, and the stumps left to dry. After a few weeks these 
stumps will burn like oil pots. 

Many farmers can clear their land with very little loss of time from regu- 
lar work by going about it in a systematic campaign. In an hour or two each 
evening a good many stumps can be blasted out and the work will be a pleas- 
ure. Only one man is needed. By making sure that the charges are rightly 
placed and proportioned to the stump, the roots all will be broken up so one 
man can handle them. 

Avoid working in the fumes and smoke of blasts, which 
Headache will cause headache. Also keep the explosives from touching 
Prevention the skin of your hands, by wearing gloves. 




When the charge is placed too shallow in the blasting of a stump that is newly cut or that has not 
rotted much, the top is ripped ofif, leaving many tight roots sticking high enough to catch a plow. 

35 



In removing saplings of sassafras and persimmon and stumps with long, 
tough roots that may sprout if permitted to break off in the ground, it often 
is of advantage to explode half stick charges a couple of feet under the trunks. 
This will not take out the trees, but will loosen the ground so that when they 
are pulled over in the usual way the roots all will come away. 

Be careful not to miss charges that are placed, when you are lighting fuse 
or connecting wires. Get them all as you pass the stumps they are under. 
Unfired charges are liable to weakening and damage, and are sources of danger. 




f4 






This is what the stump field should look like after the roots have been blown out. If the land is 
to be farmed, the next plowing should see every root removed. 

Stumps make good fireplace wood and kindling wood. You likely can 
sell fireplace wood in nearby towns by doing a little advertising or inquir- 
ing of people you know. Pine stumps have won a place 
in the hearts of all American farmers as kindling wood. 
Stump Disposal On nearly every farm and at nearly every home it pays 
to keep a large supply of pine roots for kindling. Don't 
destroy stumps when your wood-house is empty. 
At many points roots can be sold as fuel for engines. In many parts of 
the South stumps can be sold for turpentine extraction. Everyone should make 
an effort to sell or to use his stumps rather than to destroy them. They 
represent real fuel value, and a little effort usually will get it out. The 
home kindling pile can be made big enough to last for years. The roots are 
ready-cut kindling of the best grade. As fireplace wood they are superior to 
top growth, because of mineral elements in the sap. They make as good 
fuel for lime kilns as any other wood. Thf price for home use near large cities 
often is upward of $8 to $12 a cord. For turpentine extraction the roots are 
worth at least $3.50 a cord. Farmers themselves can afford to pay at least 
$1.50 a cord, with the cost of hauling added, rather than to burn the stumps. 
But when stumps cannot be sold or used they must be burned on the 
ground. Where they have been pulled out, without breaking up with explo- 
sives, and are large, the pulling engine or horses must be used to pile them, 
with the help of a derrick or gin-pole. An engine and a winch, using a cable, 
is a very good outfit for this purpose. A derrick may be a tripod with legs up 
to 40 to 45 feet long, or it may be a swinging boom derrick, with mast up to 

36 




-"-^i^ # 




Wood is a very expensive commodity in many parts of this country to-day. It never will 
get cheaper. Utilization of all parts of the trees that are cut dovra in land clearing is the thing to do 
whenever it is possible. 

30 feet high and boom 25 feet long. Let the mast lean a little toward the 
pile of stumps, so the boom will swing round itself with its load. Another 
good machine is the Conrath portable piler, much used in Wisconsin. It 
requires 10 pieces of timber or poles, of which the largest, the two skids and 
the boom, are 20 to 22 feet long. A gin-pole may be any height that is 
convenient. An old dead tree makes a good one. Let it burn with the 

stumps piled about it. With 150 
feet of half-inch cable and a pair 
of double blocks the piling can be 
done with horses. 

A better way to handle stumps 
than with a derrick is to use small 
charges of explosives to break them 
up after they are pulled. When 
stumps are well blasted the problem 
of disposal is simple. 

Start numerous small fires and 
haul and pile the roots on as they 
burn down. The fires can be kept 
going till all the roots are burned 
up, by putting on new roots and by 
shoving in butts. Have a wagon or 
sled and keep hauling and unload- 
ing all the time. Drive about the 
clearing on regular routes, each time 
making larger circles and throwing 
off a few roots as you pass by each 
fire. One man can clean up more 
acreage in this way in an equal 
The ideal size and kind of pile for burning ti^e than several men working to 

stumps and roots. These piles can be built by hand, ., , . i-i -i -i 

in unloading the stumps from a low wagon or sled. pile the Stumps in nigh piles With 

Ihem%lLT ^" "'""'^^ ^""^ "°'' '""'' *'*^ *° '"''" a derrick, except in cases where 

37 




the stumps are large and unbroken, or are left in very large pieces. What 
saves expense is piling by hand. 

When you clear land by blasting, postpone all burning of brush, logs, etc., 
till after the stumps are blasted. Then have a grand burning of everything 
at once. But do not burn the surface — don't let the fire run over the ground. 
Keep it striclily to the boundaries of the piles. There is a whole lot of fertil- 
izer in the layer of leaves, moss, twigs and other vegetable matter that every 
piece of cut-over or logged-off land has on the surface. It is foolishness to 
destroy this. Plow it down. It is worth a good many dollars on every acre. 

When you burn a clearing, first get in touch with the fire warden of the 
district if there is any forested land at all near your place. Use every precaution 
to prevent the fire from getting out of your clearing and beyond your control. 

You will hear — once in a long while — some man say that blasting out 

stumps hurts the soil. When you do, tell him he is mistaken. Proper blasting 

is beneficial to the soil. It is so beneficial that on thousands 

of farms subsoil blasting is regarded as a standard practice. 

Blasting In many orchard sections no one thinks of planting fruit or 

Benefits Soil shade trees without first preparing the ground for them by 

blasting. There is a bulletin published on that subject which 

you should have if you are interested. 

It is proper to add here, however, that when the ground is wet a blast 
does not produce the same effect in it as when it is dry. Subsoil blasting must 
be done when the ground is dry enough to crumble. Blasting a heavy soil 



^£t 




mMM 




^^^^mS^9l^9m 


BR^P^^^Hb^BH 


..^s-^^Pir 


* - "■ ' tt. ' 7 ' "' 


■p' ^ / ■:, 


- I 



A good method of piling certain kinds of green roots. Piles even as large as this will prove to be 
more expensive than smaller piles in nearly every instance, and this method is justified only when stumps 
that do not bum well, such as green cypress, pine and fir, have to be burned quickly. 

that is in a plastic condition will make it more compact instead of loosen- 
ing it. It is possible to do damage to a spot in a cultivated field by making a 
hole there — by digging out a stump, pulling a stump or blasting out a stump — 
and failing to fill it up level with the surrounding surface. 

This bulletin states, correctly, that explosives take stumps out most 
efficiently when the ground is moist. While this is true, if you want to 
secure subsoiling benefit to the land at the same time you blast out stumps, 

38 



you must do the work when the ground is at least reasonably dry. By blasting 
the stumps when the soil is not wet you sacrifice some of the efficiency of the 
explosives in the stump removing, and gain in fertility. 

Don't allow the second growth to start at all. Pasture the land with 
what stock you have. To get goats especially for the purpose is practicable 
on large tracts, but the small tract had better 
be pastured by the cattle or hogs or sheep that the farm 
Clearing Sprouts already has. Goat clearing is advisable only where time 
is plenty and money for development is scarce. Cut 
brush to the ground when it is in full leaf. Do the grub- 
bing at intervals through the summer, as time permits. Remember that the 
grubbing must be deep to kill the roots — a foot down at least. 




In this operation four men and five horses are used to pile the stumps. The gin-pole is a modi- 
fication of the swinging boom derrick. The operation is rather expensive owing to its comparative 
inefliciency compared to hand-handUng of the stumps when they are well broken. 



After the stumps and sprouts are off the land, there still is some work to 

do before it is ready for crops. New land is fertile, but it usually needs lime. 

The unevenness and stump holes should be filled after 

the plowing is done. A small horse scraper is a valuable 

Finishing Up implement for this, but anything made like a King split-log 

New Lands road drag will do the work. Make a complete job of the 

leveling. Scrape the bumps into the hollows, and make the 

surface as even as possible, so that no water will stand 

in pools. This leveling should be done carefully in old cultivated fields as well 

as in new ground. 

To take full advantage of the big supply of plant food available in the 
soil of newly cleared land, you must plant crops that will bring in money. This 
may be a grain such as corn, but is more likely to be hay, 
cotton or fruit. 
Crops for Strawberries are pre-eminently a new land crop. They 

New Ground never do as well on old land. If you have marketing facili- 
ties for them, put your new ground in strawberries for two 
or three years. 

39 



Potatoes are another paying crop on new land. Corn bears fairly well, 
but not much better than on old land. Other quick-bearing fruits such as 
gooseberries, currants, raspberries and dewberries, do very well. Vegetables 
like tomatoes, sweet corn, water- 
melons, beets and squash, succeed 
very well. Oats is a very bad crop 
to plant because of the weeds it 
invariably helps to spring up. 

The hay crops are excellent, 
and in some of them there is a 
great deal of profit. Alfalfa is the 
best of them all. If you are plan- 
ning to plant alfalfa, wait two 
years after clearing and plowing, 
meanwhile giving the land a heavy 
application of lime and cultivating 
it in some of the other crops 
named. All the clovers are good. 
Some people like to sow clover and 
timothy mixed. 

On high land sow red clover 
and timothy; on low land alsike, 
timothy and red top grass. Soy 
beans, Canada field peas, field 
beans, cowpeas, mammoth clover 
and sweet clover, cotton and 

tobacco all will yield enormous A type of "gin-pole" used to pile stumps for 

toudccu, ail will .y '<- "-* burning. Often piling by hand in small piles is much 

crops on new ground. cheaper. 

If you have cleared in the summer, harrow and disc at once, and sow 
rye, to be plowed down the next spring if you are going to cultivate the land, 
or to be mowed if you sow grass seed. The clover should be sowed on the 
surface of the ground just as the snow leaves in the spring. If you do not 
get a good stand from the first seeding, do not be satisfied with the poor one, 
but tear it up and seed over again. You cannot afford to let new ground 
loaf. There is money in making it work. 




40 



Preparing Charges of Explosives for Firing 

A charge of explosives for the purposes of these directions is considered to 
be all the explosives needed for a single hole with cap and fuse or electric 
blasting cap properly inserted in the stick of dynamite or 
powder (see pages 44 to 45) and tamped in the hole, ready 
What a Charge is to fire. The preparation of charges is practically the 
same for all sorts of farm blasting. The slight varia- 
tions advisable to suit different kinds of work are not 
enough to call for separate treatment, since the principles are all the same. 

All who use and buy explosives should read the next chapter, beginning 
on page 51, on the nature and actions of explosives. It is only the man who 
understands all the facts mentioned there who will be able to load and blast 
with greatest ease, speed and results. 

Scope of This Chapter 

It is important for everyone who blasts to understand why he does things, 
as well as how to do them. For that reason the following discussion of the 
preparation of charges is made full and complete, with due attention to all 
the important factors involved. Details of any particular part of the operation 
can be found quickly by referring to the heading desired, as given in the index. 

Readers who may not desire a full discussion are referred to the following 
brief outline of the process. 

Be careful that explosives, cap and fuse are in perfect condition. Cut a 
length of fuse sufficient for the hole to be loaded, making the cut clean, with- 
out dragging ends, at a slight slant of, say, 30 to 45 degrees from right angle. 

Pick a cap from the little tin cap box, carefully, with your fingers, and 
slide it gently on the end of the fuse. With a proper cap crimper fasten the 
cap securely to the fuse, making the crimp close to the open end of cap. Avoid 
twisting or punching the end of fuse against the bottom of cap as well as draw- 
ing it away from the bottom. For wet work waterproof the joint of cap and 
fuse with tallow, soap or other material. Do not use thin grease or oil. 

Next punch a hole at a long slant in the side of the stick to be primed. 
Better use a wooden punch for the purpose. The handle of the cap crimper 
may be used. 

Insert the cap in the hole made as described, tie the fuse in place, and, 
for wet work, waterproof all openings in the stick. You then are ready to load. 

Provide space enough in the hole at the proper point to hold the required 
amount of explosives in a bulk that is not too long. Be sure before you start 
to press in the sticks to the bottom of the hole (see page 26) that there is enough 
clearance to permit their easy and certain entrance. Tamp fully and firmly 
up to the top of the hole. 

The charge is now ready to fire, which may be done by pressing the burn- 
ing or flaring head of a freshly scratched match against the powder in the split 
end of the fuse. 

Carrying Explosives and Supplies 

The place to keep the explosives is in the magazine or storage place, and 

not with you in the field. Carry with you in warm weather only enough for the 

job or the day, or in cold weather only as much as can be 

_j . kept warm and in condition for firing until you are through 

,?, . . loading. Keep explosives separate from caps. 

^ A good way to carry the caps, fuse and small tools is 

in a basket. Put a piece of blanket in the bottom, to keep 
41 



out dampness when the basket is on the ground. Some blasters use an 
explosives box for the purpose, putting a wood handle or double wire bale on 
it. The tight wood box probably is a little better than the basket because it 
affords somewhat more complete protection to the contents. 

Whatever the method of carrying the explosives, it should be well pro- 
tected. This consists in keeping the hot sun off it, keeping rain and fog off 
it, keeping it away from dampness of the ground, and keeping it safe from 
meddlesome people and animals. 

Many blasters prepare charges before going to the field, but it is better 
practice to carry along the tools and materials, and to put them together or 
make the primers on the spot after all the holes are made in the ground or 
rock, and when everything is ready for the firing except to put the explosive in 
place. 

These remarks are given as reminders. Full discussion of proper handling 
and storing of explosives can be found on pages 66 to 68 respectively. 

Tools and Materials Required 

The first step in preparation of charges is to assemble the following: as 
many sticks of explosive (or parts of 
stick, if charges are to be less than full 
sticks) as there are holes to be primed; 
an equal number of caps; a sufficient 
quantity of fuse; some string; a wood 
punch with an end the size of a cap for 
about 3 inches; a pair of cap crimpers; 
a pocket knife. If the holes are very 
damp or full of water you also will need 
some tallow or other waterproofing 
material. In certain cases a sharp 
hatchet or axe and a block of wood will 
be worth having. The purpose and use 
of these items will be made clear later. 




A handy box for carrying supplies to field. 



Putting Caps and Fuse Together {Making Primers) 

Fuse is described as to sizes and properties on page 65 and caps on 
pages 64 to 65. Readers who are not familiar with them should turn to 
those pages at this point. Unroll the fuse and cut off a length that will be 
enough, since fuse burns about 2 feet in a minute (there are variations — see 
page 66). 

Three feet will give you 13^ minutes or a sufficient time to get beyond 

danger under ordinary conditions. The fuse, of course, must 

be long enough to reach out of the mouth of the hole when the 

The Fuse charge is in place. Measure the depth of the hole before you 

cut the fuse. 

Warm cold fuse before attempting to bend it. It may be 
taken into any warm room for the purpose but should be subjected to no heat 
greater than 1 10 degrees. If for any reason you have doubts about the con- 
dition of your fuse, cut off a foot or more and try it without any cap or explo- 
sive. If it will burn properly it is all right. 

Be sure to get fresh ends both for the match and to put into the cap. If 
fuse has been cut for some time into lengths, it is well to cut off short pieces 
from the old ends in order to bring fresh powder right to the tips. 

42 



Cutting the Fuse 



Cut the fuse off at a very slight angle or bevel — say 30 to 45 degrees, as 
shown in the diagram. This slant is for the purpose of giving a little space 
between the actual end of the powder and the explosive 
material in the bottom of the cap, to enable the spark 
to spit into material 

The only way to regulate the space is to cut the 

fuse as directed and let the long tip rest gently against 

the bottom of the cap. The spark has a better chance to ignite the explosive 

material in the cap when it spits from the end of the fuse than when it merely 

burns up to the end without any space to spit into. 

The end of the fuse where cut off should be clean and free from dragging 
ends and threads. If it is not cut off clean, part of the covering may double 
over the end of the fuse in the cap and keep the spark away from the explosive, 
causing a misfire. Be careful to keep both ends of fuse off damp ground and 
out of puddles of water. 

If the fuse has been mashed, or is too thick to go into the cap easily, do 
not peel off any of the covering. Reduce the diameter by squeezing it with 
the cap crimpers or by rolling it on a smooth surface under a knife blade or 
other smooth implement. Sometimes you can reduce it by rolling it between 
the thumb and finger. 

The very best way to cut fuse Is on a block of wood with a sharp knife. 
The blade can be pressed right through the fuse and will make a clean cut 
Another good tool is a sharp axe, to be used on a block of wood. The method 
of cutting is of small importance, just so the actual cut is made smooth and 
even enough. If you do use other tools, have a knife with you to trim up ends 
that are not true. Be careful to avoid twisting, pinching or otherwise knock- 
ing the freshly cut end of the fuse about, for you may shake out the powder 
back far enough to cause a misfire. The powder should come out flush with end. 
To get one cap out of the tin box in which they came, tilt the box up on 
edge till some of the caps slide forward, and then pick the cap up with your 
fingers. Don't attempt, on penalty of losing a hand, to take a cap out of a 
box by running a nail or a little stick or the fuse into it in the box. Be care- 
ful you do not drop a cap to the ground or floor. 

Turn the cap upside down, to make sure there is no dirt in 
it, and gently slide it on the fuse till the end of the fuse just 
touches the bottom of the cap. Do not ram, press or twist the 
end against the bottom. 

Hold the fuse with capped end up, to keep the cap from 
sliding off, and crimp the cap fast. This you do with the special plier-like 

tool called a cap crimper. The 
"crimp" is made by pinching the 
open end of the cap 
tight to the fuse. It 
Crimping should be made with- 
in the last quarter 
Inch of the open end 
of the cap. Never make it toward 
the closed end because you might 
disturb the explosive material in 
the bottom of the cap and cause it 

"Crimp" or fasten caps to fuse with a regular crimp- x. -Yr»lr>r1«» 
ing tool. This tool does the job far better than it '■" cxpioae. 
can be done in any other way. Cap CrimpcrS are Supplied by 

43 



The Cap 




all makers of explosives. Order one or more when you buy your explosive. It 
is well to have an extra one about to use in case you lose one on extensive jobs. 
This fastening of the fuse to the cap is one of the points in blasting where 
a great deal of abuse occurs. Blasters think they can take a chance with danger 
or with misfires, and attempt to crimp the caps some other way. Except in 
extreme emergency don't try to crimp a cap with anything except a regular crimp- 
ing tool; but there are times when one may not have a crimper nor be in a posi- 
tion to wait till one can be purchased. There is a way out of this difficulty 
— which is to secure a makeshift crimp with something else than a crimper. 
It is possible to use a pair of pliers, or a small pair of pincers, and accomplish 
something that may hold the cap on the fuse. The best makeshift crimp is 
to take a fold of the cap up at one side of the mouth with a pair of close 
fitting, square-nosed pliers. Be careful while doing this that you do not 
grind the end of fuse against the bottom of cap, or pull the end back from 
the bottom. If the fuse should pull away from the bottom of cap a quarter 
inch, a misfire likely would result. 




Waterproofed (tallowed) sticks ready for loading in wet holes. 






When the charge is to be placed in a dry hole, waterproofing is not needed, 
but in a wet hole the connections between fuse and cap 
must be made water-tight with tallow or soap. Do not use 
Waterproofing grease, because it may unite with the tar in the compo- 
sition of the fuse cover and soften it, when the powder train 
will be ruined. Water in the cap will surely make it worthless. 

Inserting Caps in Explosive 

The best location for a cap in a stick of explosive for farm blasting is in a 
hole in the side, about an inch and a half from one end. The best position 
for the cap at this point is at a slant that takes it in from the side toward the 
center, but as near longways, or parallel with the sides of the stick, as possible. 

44 




Crimping cap with the 
cap ciimper. 



Fuse tied firmly to stick Electric Blasting— Pass the 
with string. doubled fuze wires through 

a hole in stick of powder. 




Loop the doubled end of 
fuze wires over end of 
stick. 



Pull loop tight, bend wires 
at cap, punch slanting hole 
in stick high up and round 
to side a little. 



Insert cap in slanting hole 
to bend of wires, take up 
slack in wires. (Waterproof 
boles if ground is wet.) 




Id cutting fuse from roll 
use sharp knife. 



Taking one cap carefully 
horn box, 

45 



Inserting fresh end o£ 
fuse ia cap. 



In other words, when making the hole for 
Position of the cap in the explosive, make it with as 
Cap in Stick long a slant down toward the other end ot 

the stick as possible. There are reasons for 
this connected with superior or inferior detonation. 

Another style of priming much used is to set the cap 
in a hole made in the end of the stick of explosive, and 
then to tie the paper about the fuse or wires. This is good 
so long as it is not damaged, but experience shows that the 
tamping stick often bends the fuse over sharply when the 
primed stick is pressed into the hole and sometimes even 
interferes with the cap itself. With side priming there is 
a cushion of the soft explosive between the end of the stick 
and cap. End priming always is good provided sufficient 
care is taken in loading to prevent disturbing or displac- 
ing the fuse or cap with tamping rod. 

When all the explosive is removed from its stick 
wrappings, the cap must be inserted in the loose explo- 
sive Thi; should be done by making a hole, as in a stick But it seldom 
pays to take all the explosive out of stick wrappmgs. Nearly always you can 
leave a half stick of explosive intact for the cap. 




Bad priming. 



A good crimp. 



Making Hole 
in Explosive 



To make the hole for the cap use the handle o the cap cnmper or a 
wooden punch just a little larger than the cap. The hole should be large enough 
to let the cap in without much pressing, but should leave no 
air space about the cap. The depth of the hole also is im- 
portant. It should be just enough so that the entire cap 
can be buried in the explosive, but not any deeper. It it is 
deeper, the cap may be forced on down to the bottom, which 
will leave some of the fuse in contact with the explosive 
(may cause burning instead of exploding of powder), or the cap may be seated 
just inside the wrapping, leaving an air space at the inside end or bottom ot 
the hole, which may lower the effectiveness of the explosive. 

When the cap is seated in its hole in the side of the stick, the fuse will 
extend up along the stick past the near end. It must be tied in th^^ P°^ j^"' 
so securely that the fuse and the cap will not be pulled 
back in handling or by rubbing against the side of the hole 
when the stick is pressed down. The best way to secure 
it is to wrap a strong string several times below the point 
where the cap is inserted, then give two or three wraps 
about the fuse, and pull tight and tie; or take two loops 
about the fuse and then several wraps about the stick. 



Fastening Fuse 
to Explosive 




Cutting stick in two— roll it under knife blade 
46 



When the foregoing directions have been complied with you have a stick 
of explosive primed with a cap and fuse. It is ready to put in the hole in the 
rock or ground. 

Loading Charges in Holes 

You will need a tamping stick. This must be of wood, and had better be 
about the size of a stick of explosive, which usually will be ]}4 inches in diam- 
eter, except in case of blockhole blasting of boulders, when a smaller stick 
sometimes is needed to go in small drill holes. Never use a metal rod for 
tamping. Make sure that the hole is ready. It must be big enough to allow 
sticks of explosive to slide down easily (except in the case of small holes drilled 
in rock, when the explosive all must be taken out of the 
Tamping rod stick wrappings and crumbled and pressed into the hole). 
Loose stones, sharp stones and roots that obstruct the hole 
should be removed with a bar or spoon scraper. This work must be com- 
pleted before starting to load. If obstructions fall into the hole, after some 
of the explosive is in place, don't try to remove it by force. Make another 
hole at a safe distance from the first, put in another charge and fire it. 

Measure the hole with your tamping stick and judge if there is space for 
the required charge at the right point. Nearly always a charge of explosives 



The tamping rod should be of wcod. 

should be as much on a pile as possible. If one or 2 sticks are all the explosive 

required, it usually will not hurt to 
put them end to end. But if 3 or more 
sticks are required, to put them end to 
end makes the charge too long, and 
places the force of the blast elsewhere 
than where it should be. 

When your judgment tells you 
that the charge should be in a more or 
less round bulk, enlarge the hole at the 
point where the charge should be made. 
Sometimes this can be done by scrap- 
ing it out at the bottom with a toe-bar 
or spoon-bar. Again, if much enlarg- 
ing is required, it is well to use a small 
amount of explosive to secure it. This 
is called springing. To do this prime 
about a quarter of a stick as usual, 
and push it to the bottom of the hole. 
Use no tamping. After it is fired wait 
till the hole cools, and you will find 
a cavity large enough for your full 
charge. 

It is better to avoid springing 
holes if you can, on account of the fact 
that the cavity often is enlarged too 

much, and the surrounding earth is loosened so much as to injure confinement. 

(See page 55 on detonation). A great deal can be done by scraping the small 

auger hole out to 2 or 3 inches in diameter at the bottom and then causing the 

47 




Slitting the paper wrapping of stick to let it 
swell to fill dry hole. 



sticks to enlarge and fill the hole solidly. To accomplish this enlargement oi 
sticks, slit their wrappings 3 or 4 places lengthwise, from end to end. 1 hen 
press them home with the tamping stick. They wi 1 expand and shorten, t our 
to 6 sticks in this way can be got into the full length of two. 

Still another way is to take the explosive entirely out of the stick 
wrappings, and with the help of a tin or paper tube such, for instance, as 
calendars are mailed in, funnel it down to the bottom of the hole. But neither 
this method nor slitting the sticks is wise in wet holes It is true that 
nitroglycerin powders will stand considerable water, but the safe rule in wet 
blasting is to leave the sticks intact. Ammonia powders or dynamites will 
not stand wetting inside the paper of the sticks without damage. (Never 
under any circumstances cut. break, unwrap or punch holes in explosive that 
is frozen. You invite an explosion in your hands when you do). 

When there is more than one stick in the charge, place the primed 
stick on top of the others— put it in the hole last or next to last— when 
using the cap-and-fuse method of firing. 

Be sure that all parts of the charge are in firm contact. It will not do to 
have air spaces, or dirt, or wrinkled paper between the sticks. While all the 
powder likely would go off under these conditions, it will not do as much 
work as it should. 

The sticks of explosive may fit tightly in the holes. In that case do not 
ram or pound them, but press firmly against them, one at a time, with the 
tamping stick. Press the explosive into tight contact with the sides all round, 
at the bottom of the hole. 

Tamping 

Tamping is a necessity. The charge should be tightly confined. It is only 
in springing holes and sometimes m digging post holes that no 
tamping is advisable, and in ditching that the quantity needed is 

When the explosive is in place at the bottom of the hole, 
start the tamping by rolling in some loose ground. Keep the 
tamping stick working up and down to seat this ground against the explosive, 
though make no effort to get it tight till there is a few inches or so over the 
explosive. An exception to this rule is in the case of blockhole blasting of bou - 
ders and ledges, when damp clay tamping should be packed solid all 
the way down to the explosives. The rule for the least contents of tamping 
that will do good work is that it should be 6 or 7 times as deep as the hole meas- 
ures in diameter. 

If the tamping is less than this, the best results will not be secured, 
hence deep holes often are necessary for the sake of confinement of charge as 
well as to contain the amount of powder used. 

Hold the fuse to one side with one hand while the tamping stick is worked 
with the other hand. Rake the dirt to the mouth of the hole and be careful to 
get in the hole only earth— not clods, sticks, grass, etc. Be very careful not 
to damage the cover of the fuse with the tamping stick. 

Fill the hole to the top with tamping, and make it tight. The best material 
for tamping is moist clay. Tamping material always is better when made u)e/ 
enough to ball. In fact, there isn't much better tamping than water itselt in 
the hole, when it can be made to cover the charges deeply enough. Use the 
heaviest earth within reach, and if it is dry, better carry some water tor 
wetting it. 




Firing 

The free end of the fuse will 
stick out of the hole filled with 
tamping, say about 4 inches. Your 
remaining work is to set fire to the 
powder in the fuse, till it begins to 
spit continuously. Split the end of 
fuse with your pocket knife to 
make it light easily. Put the flar- 
ing head of a freshly scratched 
match against the powder exposed 
by the cut. 

Preparing Charges for Electric Firing (Maying Primers) 
Up to this point in the directions for preparing charges the text has spoken 
only of caps and fuse. When the firing is to be done with an electric blasting 
machine instead of fuse, you must use electric blasting caps. 

These come from the makers with the wires already fastened in them. 
(See pages 64 and 65.) They are ready to be inserted in the stick of explosive 
without any preparation such as ordinary caps and fuse require. 

Make a slanting hole in the stick of explosive just as is described on pages 
44 to 46. Into this insert the electric blasting cap, letting its wires project 
just as the fuse does when fuse is used. Then tie the wires to the stick with a 
string as fuse is tied, to prevent the cap from being pulled partly or entirely 
out of the hole. 



Stick the burning head of a match against the 
powder to light fuse surely. 





Baii inediod of fas tening wires. 
It is better to tie them. 



Bad position of cap in stick, and of cap wires. 



It is a little difficult to tie the wires tight enough with a string to prevent 
slipping. Another way to fasten them securely is to pass the wires through 
the stick. To do it punch a hole straight through the stick of explosive about 
the middle. Double the wires about 6 inches back of the cap and pass the 
doubled end through this hole. Then loop the doubled ends from the other 
side back round the lower end of the stick. Take up the slack in the wires 
and you will have a sure fastening. The cap can be inserted in the stick at 
another point, in a slanting hole, just as described previously. 

In fixing wires of electric blasting caps to sticks, avoid crossing them and 
avoid bending them sharply or in any manner that will break their insulating. 
If the insulating is broken it likely will cause a short circuit, which will result 
in a misfire. Never ta\e a half hitch about the stick loith the wires. Do not pull 
at the wires and the cap, because to do so may break the fine bridge wire that 
causes the cap to explode when the current goes through. 

49 



Load these primed sticks the same as is directed for fuse primed charges. 
Be careful to avoid rupturing the insulating on the wires with small stones in 
the hole or with the tamping rod. 

The finishing of the tamping leaves two wires projecting from each hole. 
They must be connected with the blasting machine or other source of current 
with connecting wire and leading wire, in the manner described fully on pages 
60 to 63. Further discussion is not needed at this point. 

Some General Suggestions 

In priming sticks of explosive with fuse and blasting cap, you must be 
careful to avoid permitting the fuse to touch the explosive. High explosives 
will burn like gasoline or coal-oil. They are very easily set on fire by sparks 
spitting from fuse. When they are burning the explosion will be very much 
weaker than it otherwise would be, and will give off noxious gases. 

A very frequent cause of misfires is the bending, kinking and crooking of 
fuse. This is especially frequent when the cap is inserted in the center of the 
end of the stick of explosive and then carelessly forced over against the side of 
the hole by the tamping stick and tamping material. Keep the fuse straight, 
and never under any circumstances lace it through the stick of explosive. That 
is a sure cause of trouble. 

If it becomes necessary to remove a cap from a primed stick of explosive, 
do it gently and carefully, and unless the cap and fuse are immediately to be 
inserted in another stick, destroy them both by lifting a shovelful of earth 
and putting the cap under the ground in the hole, after which light the fuse 
and go away. 

It is better not to lift or carry the primed stick of explosive by the fuse 
or wires when it can be helped. When a practice of carrying primed sticks 
by the fuse is made, misfires and poor explosions will be caused, not every 
time, but often enough to make it wiser not to do so. The cap often is pulled 
back in spite of the tie string. 

Where explosives that are subject to water damage are used in work that 
is wet, matters can be helped by making the sticks waterproof with tallow, 
paraffine or other suitable material. It is practicable to stop all the seams on 
the sticks, load and fire without delay, even with explosives that would be 
put out of business if the water got at the actual material instead of only at 
the wrappings of the sticks. Pay particular attention to waxing or tallowing 
the place where the cap and wires go into the stick. 

When doing wet blasting, use every care to keep the outer end of the fuse 
from dropping into the water or from resting on damp ground. The inner 
wrappings of fuse and the powder train itself take up water like a blotter. On 
a very foggy day it is well to keep fuse in a closed box. Mist and rain of 
course, will damage it. 



50 



Explosives and Blasting Supplies 

The catalogs of manufacturers are not intended to give all the fundamental 
facts about and the differences between the various explosives. To do so 
would take too much space. They give the trade names and the measure- 
ments and weights of sticks and boxes, demanded by purchasers, and are pre- 
pared on the supposition that blasters and buyers of explosives know what 
they need. This bulletin includes explanations of the names under which 
blasting explosives are made and marketed, outlines their properties, and makes 
clear the work and conditions for which each grade is intended and suited. 

Explosives 

There are scores of different kinds of explosives made and used for blast- 
ing purposes, and many dozens of different names used for them. The most 
familiar name of any explosive in America is dynamite. Another 
familiar term is powder. Other names are farm powder, quarry 
Names powder, contractor's powder, coal powder, stumping powder, Jud- 
son powder, gelatin, blasting gelatin, R. R. P., giant powder, blast- 
ing powder and dozens of others. 
Nearly every one of the explosives designated by these names are made 
in several strengths, and in qualities to suit varying conditions. For this rea- 
son figures and other marks are attached to the names to distinguish the grades. 
In addition to this some of the names are used to designate not only one cer- 
tain explosive but several widely different ones. This is particularly true of 
the names dynamite and powder. The selection of names in the preceding 
paragraph is made for illustrative purposes, and is not to be taken in any sense 
as a recommendation of those explosives for any purpose. The recommen- 
dations are given in detail on other pages. 

All blasting explosives are not made from the same ingredients, and they 
differ a great deal in many other ways than in quality, as quality is generally 
understood. You can buy cornmeal that is good, bad or indifferent, but when 
you buy explosives you will find there are few which can be 
classed as of poor quality. Nearly every standard kind and 
Differences grade is of excellent quality for some particular purpose and 
condition. And practically every one can be classed as of poor 
quality for conditions and purposes to which it is not suited. 
Nor is the difference one of size of stick or grain, as the case may be, though 
this is one element. The main differences are ones of strength, quickness or 
speed of gases, sensitiveness, resistance to cold and to water, density, fumes 
and cost. Some explosives are suitable for wet work, and others only for dry 
work; some are adapted to blasting hard, tough rock, others to blasting ground 
only; some freeze when chilled a little; others can be exposed freely without 
freezing. And it should be noted that many of the better explosives of to-day 
have been developed during recent years and are comparatively new. The ex- 
plosive to buy for any particular work is the best one on the market for all 
the conditions involved. 

Black blasting powder has been known and used for several hundred 
years, and it is practically the same to-day as it has been for a long time. It 
is composed of saltpeter or nitrate of soda, sulphur and char- 
coal. It does not vary in strength, and varies little in other 
Explosive properties. 

Ingredients The dynamites and high explosive powders have little or 

no relation to black blasting powder. They depend for their 
explosive force on other explosive chemicals the best known of 
51 



which are nitroglycerin and ammonium nitrate. It is not necessary in this 
brief description to name additional explosive elements. 

The first dynamite was made in Europe by mixing nitroglycerin with a 
light spongy earth, and packing the mixture in paper tubes as sticks of dyna- 
mite and powder are packed to-day. Nitroglycerin itself is a wonderfully ef- 
ficient explosive when it can be controlled, but it is so dangerous and unstable 
that it must be mixed and treated to make it safe enough to handle. 

As other explosive chemicals become better understood, it has been found 
of advantage to substitute materials that are explosive for the light earth used 
to absorb the nitroglycerin. And more than that, the nitroglycerin itself has 
been displaced to varying degrees in some of the powders and dynamites by 
ammonium nitrate and other materials. Few blasting explosives contain no 
nitroglycerin at all, but many contain only 4 or 5 per cent, of it. Each of these 
combinations of materials, or formula, has its own peculiarities in addition to 
variation in strength, all of which information it is well for a buyer and blaster 
to understand. 

The explosives marketed as "straight dynamites" and "straight powders" 
are made from nitroglycerin. Those made from an ammonium nitrate base 
are called by many manufacturers "extra" dynamites and powders. Gelatin 
dynamites and blasting gelatin are nitroglycerin explosives in which the nitro- 
glycerin has been combined with gun cotton. The various special mine, quarry, 
stumping, farm and other miscellaneous dynamites and high explosive powders 
on the market are not so named that their ingredients can be determined with- 
out a statement from their makers. 

The power of an explosive and its violence are two different qualities. 

The power, or direct strength, is due to the volume of the gases. If a pound 

of a certain explosive gives, for instance, 1,000 cubic feet 

of gas when completely detonated or fired, while a pound 

Strength and of another explosive gives 500 cubic feet and a pound of a 

Quickness third gives 2,000, the lifting power of each explosive will 

be in direct proportion to its gas volume. 

But the violence of the gases depend, not on their 
volume, but on their speed. If they are comparatively slow in forming and in 
forcing their way out of their confinement they will break out large cracks 
and escape through them, pushing the material aside. If they are very fast 
or quick, they will grind and pulverize everything they come in contact with, and 
throw out the whole side of the confining material, but will not crack it so far. 

The matter can be made clear by comparing a push with a blow of a hammer. 
Both may have equal power, but the effects on a block of wood, for instance, 
at the point where they are applied are very different. The push will move 
the object almost without marking it. The blow may move it, but it is sure 
to leave a mark of greater or less depth, depending on the nature of the ham- 
mer and its speed. A still better comparison, perhaps, is that between the blow 
of a sledge and of light hammer. It is possible to hit a blow of as much power 
or weight with one as with the other, but the material at the point where the 
blow lands with the light hammer will be badly dented, or maybe broken. 
The reason is that the light hammer moves with much greater speed. 

In quarries blasters make use of these facts in order to get the rock broken 
out in pieces of the size preferred. When they want large pieces they use an 
explosive with sufficient power to break the rock, but, comparatively speaking 
with a slow speed of gases; when they want small pieces and much shattering, 
they use an explosive of the same or greater power but with swift and violent 
gas action. 

52 



For each result and for each material a certain power is required and a 
certain quickness of the gases is best. By way of illustration, take soil blasting for 
tillage purposes. There is no object in violently grinding the earth at one spot 
while surrounding earth that might be reached is left untouched. A proper 
explosive for this purpose is one that will have enough pulverizing action, 
that will lift and shake up the soil, and that extends its effects for long distances. 
For an example of the other extreme, take mud-capping rocks. For this work 
the explosive cannot be too violent in action. The gases, backed up by the 
rapidly yielding wall of air behind them, must strike the rock a crushing blow 
in the minimum of time. 

Nitroglycerin and ammonia powders and dynamites, for all practical pur- 
poses, are of equal strengths when of equal markings. The strength is indi- 
cated accurately by percentage figures. 

Nitroglycerin explosives are uniformly quicker and more violent in action 
than ammonium nitrate explosives, and the more nitroglycerin there is in the 
explosive the quicker it is. The ammonia explosives are not as quick, in any 
strength, as the corresponding nitroglycerin explosives. Therefore a 50% 
nitroglycerin powder is more violent than a 50% ammonia powder, and a 
20% ammonia powder is much less violent than a 50% grade. 

When the object is to shatter and reduce to fine fragments the material to 
be blasted, the proper explosive is a quick one, while when the object is to 
lift and shake up the material the best explosive is a slow one. (See table on 
page 55, also detailed recommendations on pages 22 and 25.) But there 
are other factors that must be considered. 

Nitroglycerin explosives resist water better than ammonia explosives, but 
if the cartridge wrappings are not broken or opened, ammonia dynamite or 
powder can be loaded in wet holes with entire satisfaction. The firing should 
not be delayed any longer after loading than necessary, and it is wise to plan 
the work so that it may be done at the longest within a half hour after loading. 
Storage in a damp place will weaken explosives, especially ammonia explosives. 

Gelatin explosives resist water very well, and may be loaded in wet holes, 
or under water, with assurance that they will explode with their full power. 
Blasting gelatin is entirely water-resisting. 

Explosives will freeze, and when in this condition are dangerous, and can- 
not be fired properly, if at all, with a cap of any kind. They must be thawed 
and they must be handled very carefully if they are to be used. On no account 
attempt to cut the wrappings, to break a stick, or to handle the frozen explo- 
sive in the ordinary way. (See pages 56 to 58 for directions for thawing.) 

Regular nitroglycerin explosives are quickest to freeze. Others, known as 
"Low Freezing," will stand much lower temperatures without 
showing trouble in this respect. 
Freezing Ammonium nitrate explosives also will freeze, but not quite 

so quickly as nitroglycerin explosives. They too are made on 
both regular and low freezing formulas. The low freezing am- 
monia will stand more cold than the low freezing nitroglycerin. 

The regular explosives will freeze at temperatures of 45 to 50 degrees. 
The low freezing explosives will not freeze and become solid till the thermome- 
ter gets down to at least 25 degrees, and in practice many of them can be used 
right out in the open without any trouble when the temperature is down to 
zero and below. The length of time the powder is exposed to the cold has 
much to do with its freezing. 

The safety point for both low-freezing explosives and regular explosives 
is not a matter of rule, but of watching the explosive. When high explosive 

53 



powder or dynamite is frozen, the sticks will be hard, and when it is 
partly frozen they usually will have a mottled appearance on outside of the 
paper wrappings. The hardness may only be in spots. When not frozen, the 
sticks should be a little soft all over. No explosives should be handled much, 
cut, punched, rubbed, broken or loaded when they are frozen. They can- 
not be exploded satisfactorily and such acts are dangerous. 

In cold weather always use the low freezing grade of explosives, for the 
regular grades may freeze in the holes before they can be fired. It is a good plan 
to use the stronger caps, say No. 8 (see page 64) in cold weather. When 
a charge of explosive is chilled but not frozen it can be fired satisfactorily by a 
heavier impulse (blow and heat) than ordinary, such as a fresh No. 8 cap gives. 
The low freezing explosives do not differ in action from the regular explosives, 
and are just as efficient. 

The gases of explosives naturally are more or less objectionable when 
breathed. Some of them are poisonous, others are merely disagreeable. When 
explosives are used out in the open the gases are taken up by the air so quickly 
that none of them give any serious trouble, though they do cause headaches. 
It is only in tunnels and deep shafts where the air is confined that the matter of 
fumes is important, not on farms. 

Special explosives have been developed for tunnel and mine work, but they 
are not important in agricultural work. The only fact about fumes worth know- 
ing in farm blasting is that nitroglycerin explosives either 
in the form of their gases or when absorbed through the 
Other Properties skin will cause headache somewhat quicker than ammonia 
explosives. The so-called fumeless explosives always cost 
more than any ordinary dynamites and powders and are 
not suited to farm work. Farmers will do well to buy grades of explosives 
suited for their special purpose. 

Dynamites and most high explosive powders are light-colored materials 
that look like fine, sticky sawdust, and they always are packed in "sticks" 
made with cylinders of tough paper. These sticks vary in 
diameter and length. The standard is \}/i inches in diameter 
Appearance and 8 inches long. This is the size carried in stock by dealers 
of Explosives and in the magazines of the makers. You can get special 
sizes of sticks if you need a considerable quantity, varying 
from ^4, of an inch in diameter to 4 inches. Sizes other than the standard 1 ^ 
by 8 inch may cost more per pound than the standard owing to higher pack- 
ing cost. 

Dynamites and high explosive powders are packed in wooden boxes con- 
taining 25 pounds or 50 pounds, as you prefer. A 50-pound box of 20% ammonia 
powder or dynamite will contain about 105, 13^ by 8 inch sticks. If of 20% 
nitroglycerin, it will contain about 98 sticks. If of gelatin dynamite, or blasting 
gelatin, it will contain about 88 sticks. 

A word should be said here about the cost of explosives. No quotations can 
be given because the prices vary in different parts of the country and from time 
to time. The ammonia products usually are cheapest. The cost of course 
follows the percentage strength, the low percentages cheaper and the high per- 
centages dearer. Gelatin explosives cost about the same as straight nitroglycerin 
explosives. The special explosives for use in mines, tunnels, quarries, railroad 
construction work, etc., often cost more than the explosives recommended 
here for farm work. 

In buying explosives look first to getting the one that is best suited 
to the work to be done, and aside from that the cheapest one. There 

54 



would be no object in using a straight nitroglycerin or a gelatin explosive when 
one of the ammonia farm powders would do the work, for the former explosive 
cost much more than the latter. 

To avoid "explosive misfits" it is well to consider carefully the nature of 
the material to be blasted, the conditions of weather, water, etc., and the results 
wanted. The kind of explosives to use depends on these factors. Keeping in 
mind the facts mentioned in preceding paragraphs, the reader will see that there 
is a type of explosive made for almost every condition and kind of work, and 
will understand why one will not suit the work of another. 

As the briefest and clearest way of giving general suggestions for the type 
of explosive best for different agricultural work, a table follows: (Detailed 
recommendations are given on pages 21 and 25.) 

Explosives Recommended for Different Work 

Stone blasting — mudcap Straight nitroglycerin or ammonia dynamite, 

50% or 60%. 
Stone blasting — undermine ... To break, same as for mudcapping ; to throw 

out, use any dynamite or powder of 20 % strength. 
Stone blasting — blockhole .... To shatter well, any high percentage dynamite 

or powder; to break into large pieces, 20% 
ammonia dynamite or powder. 
Soil blasting — for subsoiling 

and for tree planting. ... 20 % ammonia dynamite or powder. 

Ditching — electric firing 20% to 40% ammonia explosives; (nitroglycerin 

is equally effective) ; in loose dry ground, high 
percentage nitroglycerin explosives. 
Ditching — transmitted detona- 
tion Straight nitroglycerin dynamite or powder, 50 % 

strength. 
Stump blasting — in medium 
and heavy soils, wet or 

dry 20 % nitroglycerin or ammonia dynamite or 

powder. 
Stump blasting — in dry sand 

and other light soil 50% nitroglycerin or ammonia dynamite or 

powder. 
If you are in doubt as to the best explosives for your particular work it is 
well to write to the manufacturer you prefer, asking which of their grades and 
brands would be most suitable. 

Detonation 

It is well known that black powder is fired by a spark, and that dynamites 
and high explosive powders cannot be fired by a spark but require a shock and 
heat. It is not so well known that there are great dif- 
ferences in the nature and effect of the explosion of any 
Firing, Exploding powder or dynamite, due to variations in the way it is 
or Detonating fired. 

An explosion of powder or dynamite is the result of 

a very sudden creation of a great volume of gas from a 

smaller volume of powder. The kind and amount of gases produced by any 

55 



high explosives depend on the kind and amount of shock used to fire the charge, 
and on its confinement. 

The effect of lighting a piece of unconfined dynamite with a piece of fuse 
without a cap on, is that the dynamite will burn fast without exploding and make 
a dense smoke which has a bad smell and produces severe headaches. This is 
simple combustion. If the piece of dynamite is confined closely and lighted in 
the same way it will explode, but will give off similar bad fumes. If a weak cap 
is used on the fuse, or the dynamite is set off by a fall, the dynamite will be 
partially detonated, and explode with considerable force, but it still will give 
off the bad fumes and smoke. The same piece of dynamite fired with a No. 6 
or 8 cap will be completely detonated, and will explode with great violence and 
force, even when unconfined, except by air, and will give off very little smoke. 
The last-named explosion is detonation. It is produced by a violent shock 
in connection with intense heat. Nitroglycerin is 5 times as strong as black 
blasting powder when exploded by fire, and 10 times as strong when detonated. 
This explains the enormous force given by detonation as compared to simple 
explosion. 

But detonation itself is no set thing that always takes place the same. 
There is good, or complete, or full detonation, and there is partial detonation. 
In case of incomplete detonation, or any detonation at a less speed than the 
greatest for any particular explosive, the gases formed are not what they should 
be. For one thing, they are more noxious or poisonous. The more powerful 
and severe the blow delivered by the cap, the more quickly does the chemical 
action take place in the explosive. It is only when high explosives detonate 
with their greatest speed that their maximum power is generated. 

Air spaces about the cap in the stick of explosive cushion its blow and weaken 
detonation. It is the nature of the initial detonation of the powder right around 
the cap which governs the nature of the explosion of the whole charge. A blaster 
should understand the importance of setting up complete detonation in order to 
get the greatest amount of force out of explosives. Sometimes explosives lose 
as much as 20% of their effectiveness when fired with weak caps. Lack of 
confinement has a similar effect. Sixty per cent, dynamite poorly detonated 
is less effective than 40% well detonated. 

When explosives become chilled it is difficult to detonate them properly 
with the usual cap, hence the advisability of using a very strong cap in cold 
weather— a No. 8. Many of the holes are frequently loaded for some time 
before firing, and even if the powder is soft and normal while charging, it after- 
wards becomes somewhat chilled in the cold ground. 

Throughout this and other bulletins in this series, the 

terms caps and electric blasting caps are used in speaking 
Cap Means of the exploders used to fire the charges of dynamite or 
Detonator powder, although in the field and among manufacturers 

the same articles are called by the terms "detonators," or 

"electric exploders." 

Thawing Explosives 

It has been pointed out (on page 51) that regular explosives chill or freeze 
at temperatures of 45 to 50 degrees. With the increase in the number of low 
freezing explosives that seldom need thawing, the necessity for doing the 
thawing on farms is not as frequent as it used to be. 

Frozen dynamites and powders are dangerous materials, and whenever 
the temperature is near the freezing point for them, the sticks should be 

56 



Frozen Explosive 



inspected before using to see if they show any of the hardness that indicates 
chilling. If so, handle them very carefully till they are thawed. Dynamites and 
high explosive powders will be a little soft to the pressure 
of your thumb when they are not frozen. 

Frozen explosives are dangerous because they are 
very much more easily exploded in the course of ordinary 
handling. They are more sensitive to friction and to 
blows of tools. The sticks may fexplode when dropped to the ground or 
floor, when sticks are broken in two, when wrappings are cut with a knife, when 
cap holes are punched with a stick, or when they are shoved into a hole with a 
tamping stick. At the same time they are so much less sensitive to the direct 
shock of a detonating cap that they cannot be fired properly with a cap. 
Therefore the rule must be laid down that frozen sticks of high explosives never 
must be cut or ruptured or used until they are thawed. 

When nitroglycerin freezes it crystallizes, therefore the nitroglycerin in 
dynamite or powder tends to separate from its absorbing materials into small 
crystals. When the dynamite is thawed slowly with sticks lying on their sides, 
the nitroglycerin is reabsorbed as fast as it liquefies. But when thawed too 
fast, the nitroglycerin is liable to run out of the sticks before it is reabsorbed. 
Quick thawing will damage explosives a great deal more than they would be 
damaged by freezing followed by long, gradual thawing. 

Thawing is a dangerous operation when not done 
right. It probably is correct to state that more acci- 
dents with dynamite have occurred in the course of 
improper thawing than for all other reasons put to- 
gether. At the same time proper thawing is entirely 
safe. 

Two of the most frequent causes of accidents while 
thawing explosives are in putting the sticks into water or 
steam, and putting them on hot stoves or stones. 
Water, and especially hot water, forces the nitro- 
glycerin out of the sticks. The free nitroglycerin goes 
to the bottom, and explodes at the time of the first 
increase in heat, or first light blow. When sticks of 
explosives are laid on hot material the nitroglycerin also runs from the paper 
wrappings and drops of it fall to the stone or 
Causes of metal. This almost always causes an explosion. 

Accidental Explosions At about 350 F. degrees of heat, which is only a little 
more than that of boiling water, the nitroglycerin 
will explode without a shock 

Examine your explosives a day or so before you are ready to use them, 
and if they show that they are frozen, proceed to thaw 
them in one of the following ways: Use only a DRY 
warmth. Use no temperature higher than is comfortable 
to the hand, or the limit may be set at 100 or 110 degrees. 
Use no heat of any kind that cannot be controlled with 
certainty. If you do this you will be safe. 

Every large maker of explosives will supply thawing apparatus that is 
safe. Sometimes this is a double kettle arranged so that the sticks of explosives 
can be placed in the inside vessel, while the outside vessel can be filled with 
warm water and a blanket can be spread over the top. Other more elaborate 
thawers consist of a vessel containing watertight tubes just big enough to hold 

57 




One type of thawer on 
the market. 



Safe Thawing 



sticks of explosive, running through a space to be filled with warm water. The 
catalogs describe these ready-made thawers in detail. 

Home-made thawers can be arranged with two buckets, one small enough to 
hang inside the other. Put the sticks inside the small one and warm water around 
the outside, in the big bucket. Another good way is to put a five-gallon can of 
warm water inside a barrel, or box, and pile the sticks of explosives in the barrel 
around the can. The top of the barrel should be covered with a blanket. Or 
put the water in the barrel and the explosives in a can or bucket. A small 
closet of course can be used instead of a barrel. A can of warm water can be set 
inside a magazine to keep the temperature up. 

The old-fashioned manure pile method of thawing is reliable and safe, though 
a good deal of trouble. This consists in burying a box somewhat larger than a 
box of explosives in fresh horse manure, and placing inside it the box of explo- 
sives to be thawed. A foot or more of manure must cover the box, and a small 
pipe or tube should be inserted for ventilation. The manure must be fresh. 
Allow at least 1 hours to thaw a box of dynamite or powder in this way. Twenty 
hours is better. 

The box of explosives can be taken into any warm place that is dry, but if 

this is a building you must take your own risk of fire and accident. Watch the 

box and the sticks to see if the freezing and thawing causes the sticks to leak 

free nitroglycerin. If any of this leaks out of the stick and 

gets on the floor it must be washed up according to direc- 

Sticks on Sides tions in paragraphs on storage. (Pages 67 and 68.) The 

sticks of explosives had better be piled irregularly rather 

than in tiers, for thawing. They will rise in temperature 

quicker in this way. They always must lie on their sides rather than stand 

on end. 

Electric and Fuse Firing 

The very best way to light fuse is to split the end for an inch or less, 
and stick the burning head of a 
freshly scratched match right against 
the exposed powder at the head of 
the split. This will light the fuse 
even in a strong wind. 

Where there are very many 
fuses to light in succession, as in 
subsoiling, it some- 
Fuse and times is of advantage 
Cap Firing to use a gasoline or 
other torch, holding 
the hot flame under the fuse for an instant. Whatever the method, do not 
leave till you see the fuse spitting sparks and smoke swiftly and regularly. 
Further discussion of fuse firing, except as to its adaptations, is not needed. 
Farmers who have only a few stones or stumps to blast, 
or who are planting a few trees or doing a little subsoiling. 
Electric Firing will not need any other method of firing than by caps and 
fuse. Ditch blasting in ground not watersoaked demands 
electrical firing, while the blasting of large stumps, particu- 
larly if green, and in sandy soil, as well as the blasting of large rocks, is made 
easier and cheaper by electrical firing. For large amounts of almost any blasting 
except that of tree beds, subsoiling and very small stumps and isolated small 

58 





A good reel for leading wire. 

a perfect ditch. In stump blasting several small charges very often 



boulders, the purchase of an electric blasting machine and the necessary wires is 
justified by the advantages of the electric methods of firing. 

The primary reason 
for the superiority of 
electric firing over fuse 
firing is that several 
charges may be explod- 
ed at once; the different 
charges will increase 
the effi- 
ciency of 
Advantages each other. 
Thus in 
ditching, 
you can fire many 
charges in a row and 
make 

will take a stump out better than one large charge, and in orchard, and 
garden subsoiling the simultaneous blasts frequently are of advantage. 

Electric firing is more certain when the charges are under water. The 
danger from misfires due to moisture as well as from some other cause is reduced. 
Should misfire occur, you are safe in going to the charges as soon as the wire 
is disconnected from the blasting machine. With a fuse you must wait some 
hours to be safe. When several charges, as for instance, several boulder blasts 
are to be fired, you can make one trip to safety do for the lot, instead of having 
to travel back and forward for each shot. Finally, the intelligent and careful 
use of electric firing, with its possibilities of two or more small charges doing the 
work of one large one, and its other economies, will save considerable ex- 
plosives. 

All the makers of explosives supply electric blasting machines. The ma- 
chines are small boxes of wood or metal, containing a modified magneto with a 

handle on top that you either push down or pull up, 
depending on the make of machine, to operate and 
Electric Machine to fire the charges. The machines are made in vari- 

ous sizes and capacities to fire 3, 10, 30, or more 
charges at once. The 10 charge machine weighs 
about 10 pounds. Full directions for operating and caring for the machines 
always accompany them. 

For electric firing, in addition to the machine, you will need electric blasting 
caps, connecting wire and leading wire. The leading wire is copper wire large 




Duplex Leading Wire. (Actual size.) 



enough to carry the amount of current required for the number of charges to be 
fired simultaneously. It is covered with insulating material, and is made strong 

and durable to stand much use. To make the circuit from the 
Wiring blasting machine to and through the charges and back again, 

you must have two strands of leading wire. It comes from the 
59 



explosive makers in single-strand 
form, which must be doubled, and 
in what they call duplex form, which 
has two strands of insulated wire 
twisted together or wrapped to- 
gether under one cover. 

The two small copper wires that 
are fixed in the electric blasting caps 
( see page 64) should be long enough 
to reach out of the holes. They may 
be bought in a 
Electric variety of lengths, 

Blasting Caps but 4 or 6 feet 

are regarded as Connecting wire comes on spools. 

standard. If the charges are close enough together so the wires can be con- 
nected, no connecting wire will be needed; but whenever the distance between 
is more, the charges must be connected, and connecting wire is the right thing 
to do it with. There is no particular limit for the distance between charges 
that may be connected for firing together, up to 25 feet or more. 




A very bad connection — a cause of misfires. 




Good connection for electric cap wires. 




Good connection for small cap wires and large leading wire. 



The diagrams in these pages will show how to make electric wire connections. 
Cut away the insulating on the wire ends and wrap the ends together tight. 
Wrap them for two inches. Looping the wires will not do. Be careful to 
scrape with a knife or stone the wire ends to make them bright before wrap- 
ping them together. Corroded or dirty connections are a cause of misfires. 

If the leading wire gets broken and must be 
Wire Connections spliced, solder the connection after wrapping the 

ends together, then wrap the joint with tape to 

60 




insulate it. Ordinary tire-tape is good, but a better way is to wrap the joints 

with special rubber tape under- 
neath and to cover this with the 
tire-tape. 

When only one charge is to 
be fired, connect the ends of the 
2 strands of the leading wire to 
the 2 electric blasting cap wires 
and connect the other leading 
wire end to the blasting machine 
posts. The connection with the 

Tape for wrapping joints and broken insulating. 1 i. • 1 Ll i." L* L IJ 

electrical blasting machine should 
be made the last thing before firing, after you are sure that the charges are all 
ready and after every person and animal is out of the way of the flying pieces. 
When the blast is all connected together ready to fire, except attaching the 
leading wire to the machine, give the handle of the machine one or two light 
strokes, to make sure that it is working smoothly and to charge the magnets. 
Then attach the leading wires to the binding posts on the machine, making 
sure that both the binding posts and the wires are bright and clean where they 
come together. Raise the handle of the machine to its full height and push it 
down with speed. When the handle starts on its downward stroke, the pinion 
immediately clutches the armature and starts the generation of current. The 
current, growing stronger as the stroke proceeds, causes considerable resistance 
toward the end of the stroke. The current generated is directly in proportion 
to the speed with which the handle is pushed down, especially just before reach- 
ing the bottom. Any let up toward the bottom will cause a drop in the current 
and may result in misfires. Therefore, make it an invariable rule, whether the 
shot be large or small, to bang the handle down hard and carry the stroke with 
all possible speed to the bottom. Try to knock the bottom out of the box. 
Machines which operate by the twisting of a handle must be handled equally 
quick. 



Very best wire connection, ready for soldering if need be. (Excellent for leading wire.^ 

When more than one charge is to be fired the different charges must be 
connected together. The diagrams will help you to understand how this should 
be done. For nearly all agricultural blasting the connection in one series is the 
best — that is, connecting each charge to the next one and so on until they are 
all joined, with one loose electric blasting cap wire from the two end charges 
of the series. (See diagram A and D, page 62.) 

Once in a while, where the series is long and the charges are in a line, you 
can arrange to have the 2 loose wires at the same end of the series by making 
the connection, not to each next charge in the row, but to the one beyond and at 
the farther end doubling back and connecting the missed charge. Do not use 
this method where it involves many splices with connecting wire. 

Connections in parallel sometimes are desirable in the case of ditches, or 
other extensive blasting. To make them run a piece of wire away from one lead- 
ing wire strand along the lines of charges and connect one wire to each charge. 
Then run another similar piece of connecting wire connected to the other strand 
of leading wire, and attach to it the other cap wire of each charge. 

But to fire charges by means of parallel connections takes so much electric 
current that a blasting machine cannot be used. Generally speaking, parallel 

61 



'yi^yj^^:^''-^) 



:^ 



K^i 




A straight ser-ieS connection for 

U5& with bia sting machine 




>ing into two circuits to reduce 
resistance: used with b'asting machine 



C Multiple -Series used with both 
blasting machine and power-current 



Method of wrapping wires together to make electrical joint, and of taping joint. 

connections require current from an electric light or power plant. If your 
work is such that the charges cannot be connected in series or that parallel 
connections are desirable, it is well to communicate with an expert or authority 
on electricity for special sugges- 
tions and advice as to how best 
to fire your charges. 

In a bulletin of this size it is 
impossible to give a comprehen- 
sive statement of 
Current electric firing. But 

Required to give some idea, 
it can be stated 
that an electric blasting cap re- 
quires I to 1 3^^ amperes to insure 
firing. This amount of current will 
fire one cap or many in a series. 
To force this amount of current 
through the wires requires a 
certain voltage, the amount de- 
pending on the size and length of 
all the wires, and on the joints. 
One bad or poorly wrapped joint 
will increase the resistance of the 
circuit more than several caps. 
The voltage of the current re- 
quired to fire any circuit usually 
can be computed by an expert 
when the details of the wiring 
system are explained to him. 

When charges are connected 
in parallel, instead of series, or in 
multiple series (see diagram C), 
each circuit requires 1 to 13^2 
amperes of current. That is, each 
cap requires 1 to 13^2 amperes 
when connected in parallel. The 
voltage required, of course, de- 
pends on the resistance of the 
wires. A very much greater cur- 
rent than of I to 1 3^ amperes will 
do no harm; in fact it is desirable. 

Electric blasting machines 
are constructed to give a suffi- 
cient amperage and voltage for 




^ Three wire system with thr^e-pcst 
blasting machine 'B' used with two-post 
msrchine is better 




/T Parallel connection, used with 
electric light on power-current 




C^ T,vo delona/ors in C - ,— 

3/ro^e. w/r^d in series, /n 3 /7o/e,wiredin G^ Picking up sepersfe holes 

not sogood,3sfi3r<3//el. p^railei/ best i*'^_y in series, not recomfnended. 

C... Combinations of parai/e/ circuits 
when firing with e/ectric li^ht or 
power current. 



Ways of connecting up charges for electric firing. 

62 




Two post electric blasting 

machine — push down 

type. 



firing properly the number of caps specified as the capacity of the machine 
when connected in a series. If too many caps, or more than usual wiring 
is connected to any machine, misfires will result. Other current can be 
used in place of that supplied by a machine, provided it 
has enough and not too much amperage and voltage. 
Too great a current will burn out wires without firing all 
the charges. Too little current sometimes will do the 
same, or it may do nothing. In emergencies dry cells or 
wet batteries can be used by skillful operators to fire a 
few charges, when great care is taken to have the wiring 
arranged for the purpose. Before attempting to fire 
charges with batteries of any kind, learn the amperage 
and voltage of their output and see that your shots come 
within their limits. The use of batteries is more ex- 
pensive than the use of electric blasting machines. 

Bare connections at the charges or back along the 
leading wire should be raised off the ground by stones, 
sticks or piles of dirt placed under insulated parts of the 
wires at each side of the splice. During a thunder storm, do 
not stand near any of the charges that have been connected. Avoid dragging the 
leading wire over bareor rough ground as much as possible, and particularly avoid 
kinking it. Be careful not to break or tear or scratch the insulating of any wires. 
Do not attempt to fire through a long length of leading wire wound in a coil 
or on a reel. The induction, leakage or short circuit of current in the coil 
of wire causes the blasting machine to deliver a slow discharge, which is fatal to 
proper firing. Leading wire that is watersoaked or that is covered with mud 
will lose a considerable part of its current. 

Misfires 

Nearly half of the accidents noted each year in blasting operations are the 
result of attempting to examine misfires too soon. If misfires occur with fuse 
firing, stay away from the shot at least 2 hours. It is better to wait until the 
next day, for the spark may linger 24 hours and still cause an explosion. (See 
page 59.) Rock and stump misfires are to be avoided especially. When you are 
firing the charges electrically, you may approach the shot with entire safety as 
soon as the lead wire is disconnected from the blasting machine. 

Misfires are due to the following named causes. The remedies for them are 
care in preparing the charges and in loading, the details of which are given in 
the proper chapters. 

With cap and fuse firing, misfires are caused by having the end of fuse 
pulled back a little from the bottom of the cap, by crimping the fuse too tightly 
with a groove crimp and shutting off the spark, by damp or wet fuse, especially 
at the end of the cap, by defective cap, by the cap getting pulled out of the 
explosive, by kinked, damaged, broken or pinched fuse, by failure to light fuse. 
A great many misfires were never fired at all. With electric firing the reasons 
for misfires may be damaged wires in the hole, causing short circuits, defective 
caps, overloaded blasting machine, cap pulled out of explosive, bad wire con- 
nection at some point, or broken wire. 

If you find after due time that for some reason the charge cannot be fired 
by lighting the old fuse or by sending current through the wires, you must deal 
with a real misfire. 

The best thing to do is to put in another, lighter charge in a new hole made 
6 to 1 2 inches of the original one. The explosion of the new charge will explode 

63 



This high explosive usually is fulminate 



the old one. Never touch the tamping in the old hole unless you know just how 
deep it is, or how many inches of it there are above the charge. Once in a 
while the tamping rnay be dug out of a blockhole misfire. It seldom pays to do 
this in stump blasting, and never in ditching, or soil blasting. At best it is a 
dangerous operation. Mudcap charges can be opened and new primers inserted 
without danger or difficulty. This should be done by removing part of the 
mud at another point, and inserting a new cap and fuse, or electric blasting 
cap, as the case may be. 

Cap (Detonators) 

Blasting caps are little copper tubes closed at one end, 1}/^ to 2 inches long 
and something less than a quarter of an inch in diameter. At the bottom is 
placed several grains of a high explosiv^ that is very powerful and exceedingly 
sensitive to heat, shock and friction 
of mercury, but often is other? 
material. They are packed in small 
tin boxes, open end up, usually 1 00 
to the box. 

The purpose of the blasting 
cap is to supply the shock and heat 
necessary to detonate the charge 
of dynamite or powder to be fired. 
If it were not for safety in handling 
blasting explosives, they all could 
be made as sensitive as the material 
in the caps. But such explosives 
would be impossible to handle 
without accident. In fact, it would 
be impossible to handle the little 
bit of explosive in the caps if it 
was not protected by the copper 
shells. Even at that caps must be 
kept free from jars and from heat 
and sparks to avoid premature 
explosion. 

The strength of caps is care- 
fully regulated by the makers to 
fire the dynamites and powders on 
the market. The explosive material 
with which the caps are loaded is such as will deliver a shock and a degree of 
heat of the strength and violence required. The caps are numbered according 
to strength. All dynamites and powders used for agricultural blasting require 
at least a No. 6 cap. If they are chilled a little, but not frozen, they require 
No. 8. It is the part of wisdom to use No. 8 caps all the time if you can get 
them. They give you a margin of strength should moisture or other causes 
weaken them in storage. 

Blasting caps must be used with fuse. And before they are inserted in the 
stick of explosive they must be fixed to the fuse properly. (See pages 43 to 46.) 
It is the spark which travels down the fuse that fires the cap. 

Electric blasting caps are made on the same principle as ordinary blasting 
caps. They have the copper tube, the explosive at the bottom, etc., but they 
differ in the way this explosive is fired. Instead of by a powder spark they are 
fired by a red-hot wire that is heated by an electric current. 

64 



ggsJ^nami*'****' 


-"=;>«;» ,J5^__ 




i 


/ 1 




: 


1 


1 


1 


;^» 




'1 


t 


ll 


r 


1 1 




^1] 1 








IJi- . 


.^> 


1 


D E 


' G 


7 
1 


f," 



D and E are ordinary blasting caps ; F and G are 
electric blasting caps, often called fuzes. 




Electric blasting cap or fuze. 

Every electric blasting cap has fitted in it 2 small copper wires, which 
must be considered part of the cap. Down near the bottom of the cap is a deli- 
cate bridge of finer wire. The entire arrangement is held in adjustment and 
sealed by a casting of sulphur-like substance. 

D, Av 




e: d 

The interior construction of an electric blasting cap or fuze. 

For fuse blasting you must use regular blasting caps, and for electric blasting 
you must use electric blasting caps. It is impossible to substitute one for the 
other. Never pull at the wires in an electric cap. It is dangerous and may loosen 
or throw out of adjustment the arrangement of wires inside. And never try to 
dig out the wires of an electric cap or to dig or to punch the explosive in the 
bottom of a blasting cap. 

Fuse (Safety Fuse) 

Fuse is used for firing black blasting powder and for firing dynamite and 
high explosive powders through the medium of a cap. It is made by enclosing 

within a covering a train of special 
black powder and an inflammable 
cotton string. The spark runs 
down this powder train. 

The powder used in fuse is 
specially made for the purpose, is 
pulverized and is highly compressed 
by the covering of the fuse. The 
covering itself is made of varying 
materials, depending on the condi- 
tions under which the fuse is to be 
used. For dry work it is only 
enough to hold the powder in place 
and to keep the powder train from 
getting broken. For damp and wet 
work it is made waterproof by in- 
Fuse as it comes in rolls. creasing the number of layers in 

the covering and by adding varnish, coal tar, as other waterproofing material. 
There are many brands of fuse on the market. In buying fuse you must 
bear in mind the character of your work. For work that is en- 
Grades tirely dry you can use ordinary cotton or hemp fuse with satis- 
faction, if it is large enough to fit a blasting cap snugly. 
For work in damp ground, use a fuse in which the cotton or hemp is covered 
with one layer of waterproof tape or other material. This is called single-tape 
grade or may be known by brand name only. For work where the ground is 
wet, such as in stump and stone blasting in damp or wet weather, use a double- 
covered fuse — fuse that has two layers of tape or other material over the cotton 

65 




covering and waterproofing material added. For work where water covers the 
charges it is best to use fuse with three layers of tape or other material and 
full waterproofing. This is called triple-tape fuse or may have special brand 
names. When buying fuse for general farm work, it is well to get a water- 
proof grade, since it can be used for both wet and dry work. 

Most reliable fuse burns about 2 feet per minute when in perfect condition. 

If it becomes damp, it burns much slower. Cases have been known 

where the spark smouldered in damp fuse for hours without 

Rate of traveling more than a few inches. Another source of uncertainty 

Burning is where fuse has been pinched. It may take the spark a minute 

or an hour or a day to get past the pinched point. 

When fuse is cold, it is hard and brittle, and may crack open 
when unrolled. If it gets too warm, its waterproofing material may penetrate 
to the powder train inside and ruin it; or the covering may first soften and then 
harden, in this condition breaking as though cold when unrolled. If grease is 
allowed on the cover it may combine with the waterproofing and ruin the 
powder inside. 

Handling Explosives 

Dynamites and powders in boxes can be hauled freely in spring wagons. 
You should see that no bolt heads or other metal parts project from the wagon 
boxes to strike the boxes of explosives. Sweep all dirt out of the wagon. Have 
the beds clean or covered with straw or blankets. 

Go over your wagon and harness before you load dynamite to make sure 
they will not break down while you have the explosive aboard. Be sure you 
have the hitching straps or tie-ropes along, and do not leave the horses standing 
without tieing them securely. Break no colts while hauling explosives. If 
you use a motor, stop it and set the brake tight before you leave the load. 
In driving through a town stay away from dangerous crossings. 

Keep the sticks of explosive in their original boxes until you are ready to 
use them. Don't have them around loose. In carrying them to the field, use 
a wood basket or a box and not a metal bucket. Always protect explosives from 
all possibility of being reached by falling sparks or from match heads or other 
source of fire. Rain, hot sun and the like must be kept away from explosives. 
Use care to lay sticks or set the boxes or baskets containing explosives where they 
will not fall down, be blown over by wind or knocked over by careless people 
or by animals. Cattle will eat sticks of dynamite, or powder, because of their 
sweet and salty taste. The explosive will make them sick, sometimes kill them. 

Since nitroglycerin often will cause headache when absorbed through the 
skin it is best to wear gloves when handling the sticks. For this same reason 
some people punch holes for caps in the sticks with a piece of wood rather than 
with the handle of the cap crimper. 

Caps should not be carried in the same basket or box as explosive, but should 
be carried separately. Take only enough along to do the work in view and 
carry them in the tin boxes they come in. Many serious accidents have been 
caused by blasters having loose caps in their pockets during work or afterwards. 
Sooner or later a chance jar is likely to set them off. When several caps have 
been taken out of the little tin box in which they come the rest will be loose and 
will rattle about. This should be stopped by filling up the empty space with 
paper. 

The handling of caps is not dangerous provided you do it intelligently and 
with care. Keep them safe from any jars or heat. You can sometimes do 

66 



many foolish things with dynamite and powder without 

serious results to yourself, but not with caps. Letting a cap 

Handling fall to the ground or floor likely will cause it to explode. For 

this reason you should keep the caps and explosives apart, 

in hauling, storing, and handling, bringing them together 

only at the last minute before you prepare the charge to be loaded in the hole. 

One cap can produce an explosion powerful enough to tear your hands off. 

Electric blasting caps must be handled with the same care as regular 
blasting caps. All caps must be protected from dampness during handling. No 
trouble will be experienced if you use common sense at every turn, but thought- 
lessness and carelessness in the handling of explosives will cause disaster. Bear 
in mind that when an accident happens with an explosive there is no time to 
save yourself, and no afterthought will prevent serious injury to you. Fore- 
thought is the thing with explosives. In an explosive you are handling an enor- 
mous strength. The fact that it occupies small bulk now should not interfere 
with your imagining it as an enormous engine with power enough to crush you 
easily, but under entire control if you do your part right. 



Storing Explosives and Supplies 

The storing of dynamites and powders on farms offers no serious problems, 
though it may call for some shifting of arrangements to meet proper require- 
ments. The explosive must be kept dry. They should be kept cool. This means 
that any ordinary temperature of the air is all right, except that in hot weather 
the room where the explosive is kept should not get warmer than 80 or 90 
degrees. If it is properly vendlated day and night it will not. Probably the 
best common storage place for explosive is in an outbuilding under the floor of 
which the air circulates freely and with a ceiling between the room and the roof. 
It should be strong, and should be provided with a lock. A responsible person 
should have charge of the key at all times. 

The explosive should not be kept in a garret, because the hot sun beating 
down on a roof will raise the temperature under the roof away past the 100 
degree mark. 

Dampness is injurious to explosives, as noted on page 44, and dynamites 
and powders must be kept where moist air will not surround them. The ideal 
storage would be fireproof, but since this is out of the question on the average 
farm, the best that can be done in that respect is to guard against fire. It is 
well to make sure that the explosive is out of reach of any stray or malicious 
bullet that might be fired into it. 

Look to your insurance policies and see whether they provide against the 
storage of explosives in any of your buildings. Store the explosive in a building 
not covered by the insurance. 

Where large quantities of explosives are to be stored as a regular thing, 

or for any length of time, it is advisable to consult the makers 

of explosives or others experienced in their handling in regard 

Magazines to the location and construction of a magazine. A magazine 

can be set up cheaply and can be made fireproof, bullet proof, 

thief proof, well ventilated, dry and safe in every way. It 

should be built of brick. Any explosive maker will furnish plans without 

charge. In any case explosives should be stored at least 50 yards away from 

any other buildings and from roads or railroads. 

67 



Blasting caps of any kind must not be stored with dynamite or powder. 

Fuse is not explosive and can be stored with dynamite or powder. 

p Blasting caps are even more subject to damage by moisture than 

P explosive and must be stored accordingly. Caps must not be allowed 

to become heated. 

A statement of the ways in which explosive deteriorates will help in 

selecting a proper storage place for it. In temperatures higher than 80 degrees 

troubles may begin. Long continued temperatures of 

90 to 100 degrees may cause the nitroglycerin to leak 

Deterioration out of the absorbing material and to gather inside the 

wrapping on the lower side of the sticks, or may even 

cause it to leak out of the wrappings through the 

boxes and to the floor. 

Strict watch should be kept of the sticks and the boxes to catch any such 
condition. If leakage occurs, turn the explosive over and reduce the temper- 
ature. Burn the empty boxes one or two at a time out away from buildings, 
and scrub the floor where the leakage occurred with a strong solution of sal 
soda. This will decompose the nitroglycerin. If it becomes necessary to de- 
stroy a little explosive without detonating it, the job can be done by immersing 
it until dissolved in such a solution, stirring it gently with a wood paddle. 

If the sticks feel smeary it is possible they are leaking. The test is to lay 
them on white paper for a little while. If they are leaking they will stain the 
paper, otherwise not. 

At a temperature of 105 degrees nitroglycerin explosives will lose 10% of 
their strength in a few days by evaporation. Repeated freezing and thawing 
is bad for explosives, especially if the thawing is rapid. Slow thawing will not 
damage them much. After explosive once is frozen and thawed, it will freeze 
much easier again. 

When stored for many months explosives are liable to decomposition of 
some of their elements, especially if they get damp or too warm. One of the 
marks of this is greenish stains inside the stick wrappings. No length of time can 
be stated for the keeping of explosives, because it practically all depends on 
conditions. Under favorable conditions most dynamites and powders will re- 
main in good shape for years. Again, a month of improper storage will ruin 
them and make them dangerous to handle. They develop troubles sooner in 
the light than in the dark. 

Deteriorated explosives are likely to be dangerous — far more so than normal 
explosive. Keep watch over what you have in stock. Maintain proper conditions 
as far as possible, but if they show troubles do not hesitate to condemn them. 

Shipping Explosives 

The shipping of high explosives is controlled by the Interstate Commerce 
Commission, and the rules and regulations are very strict and rigid. Most of 
them are embodied in an Act of Congress of March 4, 1 909, and violations are 
punishable with fines of not more than $2,000, or imprisonment for not more 
than eighteen months, or both. The person making the shipment is 
responsible. 

A copy of the rules and regulations can be secured from the Bureau of 
Explosives, Underwood Building, New York City, or can be read at any freight 
station where there is an agent. 

The rules provide that no explosives (other than certain exceptions named) 
shall be carried on any train, boat, trolley, or other vehicle carrying passengers 

68 



for hire, and that no explosives under deceptive or false markings or under- 
standing shall be delivered to a common carrier; and further, that all other 
regulations shall be complied with. 

In shipping by railroad no caps or detonators of any kind can be sent in 
the same car with explosives. In practice the railroads usually send them by 
another train, which works out to be another day in the cases of nearly all 
shipments. This is responsible for some delay in delivery of explosive ship- 
ments. Do not expect to have explosives come through as quickly as you would 
other freight. 

Explosives cannot be shipped by express or by mail, but are sent by 
freight, the same as groceries or dry goods. The railroad company is required 
to place the packages in a certain way inside the car and to brace them with 
lumber. In case of car-lot shipments the shipper must furnish this lumber and 
do the bracing. 

The regulations provide that railroads must have 24 hours' notice of ship- 
ment of explosives, and that shipments must be removed from the receiving station 
within 24 hours of their arrival there. The packages must be plainly stenciled 
with the name of shipper and consignee, and bills of lading must conform with 
certain specifications. 

Empty boxes which once have contained explosives must never again be 
used for shipments of any kind. Farmers who have attempted to ship vegetables 
or other farm products in such boxes have unwittingly gotten themselves into 
trouble on account of this regulation more than once. 

Danger and Safety 

Modern explosives have been developed to the point where they need not 
be feared by anyone who handles them intelligently. Speaking in a comparative 
way, they may be used with no greater dangers than there is in the using of 
horses, mowers, traction engines, sawmills, or other farm equipment, or than 
there is in using shotguns or rifles. 

The general use of explosives on farms is so new that many people dis- 
trust them more because of their newness than from a clear understanding of 
any actual dangers their use may hold. A review of what the dangers are may 
help users of explosives to avoid them, and may help to build up the reader's 
belief in the safety of explosives. 

There is some danger in the handling and transporting of explosives, but 
it depends very largely on the exposure of the dynamite or powder to heat, 
flame, sparks, blows and friction. The directions say to keep explosives dry, 
to keep them at a temperature less than 90 or 100 degrees F., to keep them 
safe from sparks, and to avoid blows and shocks. If these directions are followed 
there will be few accidents. 

Probably the most common cause of accidents with explosives lies in 
violation of some of these primary rules while thawing frozen sticks of dynamite 
or powder. Freezing makes the high explosive less sensitive to the simple 
direct shock of a blasting cap, unaccompanied, as it is, by any friction. But at 
the same time freezing makes the explosive more sensitive to friction in any form. 

For this reason, though a frozen stick of dynamite cannot be fired properly 
by a blasting cap, it is very likely to be fired prematurely by a chance light 
blow from any object touching it, by your slitting the wrapping paper with a 
knife, by breaking the stick in two, or by attempting to punch a hole into it to 
insert a cap. (These operations are entirely safe when the explosive is normal.) 
If the stick is dipped in warm water or exposed to steam, or is laid on anything 
which is warmer than about 1 25 degrees, free nitroglycerin likely will leak out 

69 



and fall in drops. And one drop of nitroglycerin falling only a few inches may be 
exploded itself and may explode all dynamite that is near it. 

Throughout the entire course of handling the explosive, from the freight 
station to the hole in the stone or the ground, you should remember the five 
cautions which will be repeated- Keep it dry, keep it cool, keep it away from 
sparks and flame, and keep it safe from blows and friction. Be careful — as 
careful as you would in driving a big automobile or a traction engine. Then 
you will be secure from any accidents, and explosives will be entirely safe to 
handle. 



70 



INDEX 

Page 

Accidents 57, 58 

Ammonia explosives 53 

Amount of explosives required 28, 29, 30 

Augers 32, 33 

Blasting compared with other methods 13, 15 

Blasting Machine 59, 62 

Blasting of stumps 7, 1 3, 2 1 , 25 

Blasting of stumps, lateral roots 23 

Blasting of stumps, semi-tap roots 23 

Blasting of stumps. When to do 21 , 22 

Blasting of stumps with tap roots 24 

Boring holes under stumps 24, 25, 26 

Boring power 26 

Boxes of explosives 54 

Breaking sticks of explosive 45, 46, 47 

Burning stump pieces 36, 37, 38 

Burning stumps 13, 16, 17, 18, 19 

Buying explosives 54 

Caps and fuse. Putting together 42, 45 

Caps, Blasting 56, 64 

Caps, Positions in sticks 44, 46, 49 

Capstan pullers 14 

Carrying explosives 41 , 66, 67 

Charges, Depth for 22, 23 

Charge, What it is 41, 49 

Charpitting 17, 18 

Chilled explosive 53, 56, 57 

Choice of methods 13 

Clearing away sprouts 39 

Clearing land. Advisability of 4 

Clearing land. Methods of. Compared 13 

Cold weather blasting 21 , 22, 53, 56 

Connections, Wire 60, 61 , 62 

Cost of explosives 54 

Cost of stump removing 6, 7, 2 1 , 32 

Crimping caps 42, 43, 44 

Crops, Increase of 6 

Crops, Kinds of for new ground 39, 40 

71 



Page 

Cultivation, Ease in 6 

Current required to fire charges 62 

Cutting sticks of explosives 45^ 46^ 47 

Danger 69 

Dead stumps 13, 23, 28, 29 

Depth for charges 22, 23 

Derricks 36, 40 

Deterioration of explosives 68 

Detonation 55 

Detonators 56, 64 

Differences in explosives 5 1 , 54 

Digging stumps 12, 17 

Disposal of stumps 13, 36 

Donkey engines 1 5, 20, 36 

Dry ground 23, 3 1 

Dynamite, General properties of 51-54 

Dynamite, Grades and types of 51, 52, 54 

Dynamite, Kinds to use 31 

Dynamite, Low freezing 53 

Dynamite, Names and brands of 51-55 

Dynamite, Removing wrappings from sticks of 41, 42, 46, 47 

Electric blasting caps. Description 49, 56, 60, 63, 64 

Electric blasting caps. Inserting in sticks 44, 45, 49 

Electric blasting, directions for 23, 24, 25, 27, 49, 58 

Electric boring machines 26 

Electric firing. Advantages of 59 

Electric firing. Machine for 59-62 

Electric firing. Wiring required for 60, 62 

End priming 46, 49 

Engines 15, 20, 36 

Explosive ingredients 51 

Explosives, Frozen 53, 56 

Explosives, General properties of 51 , 54 

Explosives, Low freezing 53 

Explosives, Names of 5 1 , 55 

Explosives, Quickness of 52 

Explosives recommended 31 , 55 

Explosives, Removing wrappings from sticks of 46, 47 

Explosives required. Amount per charge 28, 29, 30 

Explosives, Strength of 52, 53 

Explosives to use 31 , 52 

Finishing new ground 39 

Fireplace wood 36 

72 



Page 

Firing. Electric 23.24,25.27.49,58. 59 

Freezing of explosives 53, 54, 56 

Fuel value of stumps 36 

Fumes 54 

Fuse and caps. Putting together 42. 45 

Fuse cutting 42. 43 

Fuse, Fastening to sticks 44, 45, 46 

Fuse length 42 

Fuse, Lighting 49, 58 

Fuse, Safety 65 

Fuzes 49, 64, 65 

Fuzes, Priming with 45, 49, 50, 58 

Gases 54 

Gin poles for piling 36, 37, 39 

Green stumps 13, 23, 28, 29 

Ground, Dry 23, 3 1 

Ground, Nature of 12, 15, 31 

Ground. Wet 21, 22, 38 

Handling explosives 66 

Hangfires 27, 50 

Headache 35, 54, 66 

Hints. General 34 

Holes for caps in sticks 46 

Holes in ground and wood for charges 24, 25, 26 

Idaho charpitting 18 

Ingredients of explosives 51 

Labor required 32 

Lateral-root stumps 8, 9, 24, 25 

Length of fuse 42 

Lighting fuse 49, 58 

Loading charges 22,27,28,47, 48 

Logs, Splitting 35 

Loss from stumps 6 

Low freezing explosives 53 

Magazines • • • 67 

Making holes for charges 24 

Methods of clearing compared 12, 13 

Misfires 27. 50. 63 

Names of explosives 5 1 , 55 

Nature of ground 1 2. 1 5, 31 

Nitroglycerin explosives 53 

Packing of explosives 54, 68 

Parallel connections of electric wires 61 

73 



Page 

Pasture land 4, 39 

Filers 36,37. 39 

Powder, Best to use 31,55 

Powder, Grades and types of 31, 51, 52, 55 

Powder, General properties of 54 

Powder, Low freezing 53 

Powder, Removing wrappings from sticks of 46, 47 

Power boring .- 26 

Primers, Making 42, 45, 49 

Priming sticks of powder 42, 44, 45, 46, 49 

Profit in stump removal 6 

Protection of explosives 4 1 , 66, 67 

Pullers 14 

Pulling stumps 13, 19, 20, 21 

Punching sticks for caps 45, 46 

Quickness of explosives 52 

Rod tamping 47 

Roots. Nature of 8, 9. 24, 25 

Rotten stumps 1 0, 35 

Rotting of roots 10 

Safety 96 

Safety fuse 65 

Season to blast stumps 2 1 , 22, 38 

Season to pull 14, 15 

Selling stumps 36 

Semi-tap root stumps 8, 9, 23, 24, 25 

Series wire connections 62 

Shipping explosives 68 

Side priming 44, 49 

Slitting stick wrappings 27, 46, 47 

Soil auger 33 

Soil blasting 21. 22, 38 

Soil conditions 10. 13. 14, 21, 22, 31. 38 

Soil. Dry 23. 31 

Soil. Nature of 12, 15. 31 

Soil, Wet 21, 22, 38 

Spoiling of explosives 68 

Sprouts 10, 39 

Standing trees 34 

Sticks of powder. Appearance and size of 54 

Sticks of powder. Breaking or cutting .46, 47, 48 

Storing explosives 67 

Strength of explosives 52, 53 

74 



Page 

Stump blasting 7, 13, 21, 25 

Stump disposal 1 3, 36 

Stumps, Age of 10. 13, 28, 29, 30 

Stumps, Kinds of 8, 9. 24. 25 

Stumps, Lateral root and semi-tap root 8, 24, 25 

Stumps, Nature of 24, 25, 30 

Stumps, Tap-root 8, 23. 24, 25, 29. 30 

Tamping • 48 

Tamping rod 47 

Tape 61 

Tap-root stumps 8, 9, 24 

Test loadings 30, 3 1 

Thawing explosives 56, 57 

Time required for blasting •. 32 

Tools 21.32. 33 

Traction engines 1 5. 21 

Violence of explosives 52. 53 

Water in ground 10, 27. 38 

Waterproofing charges 44 

Weakening of explosives 68 

Weather conditions 10,21. 22, 31, 53, 56 

Wet soil 10, 38 

Wire connections 60, 6 1 , 62 

Wiring for electric blasting 59, 62 

Wrapper removing from stick 46. 47 






75 








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